CA1247935A - Vent-relief valve for a wet motor gerotor fuel pump - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A fuel pump vent-relief valve for venting a vapor pressure less than a fluid pressure and relieving the fluid pressure when in excess of a predetermined relief pressure includes a valve body having an inlet passage, an outlet passage, and a valve bore containing a ball valve and a tubular valve, the tubular valve and the valve body cooperating to define d relief passage between the inlet passage and the outlet passage. The pump includes a first spring located between the ball valve and the tubular valve acting to bias the ball valve towards the inlet passage and the tubular valve towards the outlet passage, the hall valve adapted to cooperate with the inlet passage to establish a vapor bypass passage therebetween when the ball valve contacts the inlet passage, and the tubular valve having a vent passage therethrough adapted to be closed by the ball valve; and a second spring located between the tubular valve and the outlet passage for biasing the tubular valve towards the inlet passage, to normally close the relief passage; such that the vapor pressure is vented through the bypass passage and the vent passage until the fluid pressure overcomes the first spring to cause the ball valve to close the vent passage and such that fluid pressure is relieved when the relief passage is opened when the fluid pressure exceeds a predetermined relief pressure to urge the tubular valve towards the outlet passage to open the relief valve.

Description

:~'2':~7~335 The present invention relates to ~uel pumps and, more particularly, to fuel pumps having relief and/or vent valves~
Wet motor fuel pumps of the gerotor type have not heretofore used vent valves fuel vapor in that such pump when rotating at its normal rate is not sufficiently efficient to pump gases such as fuel vapors as compared to liquids such as fuel gas. The generation of fuel vapors in any fuel pump is a common occurrence. Gerotors meeting less than the tightest tolerances on the tip clearances and also flatness and parallelism are unable to self prims themselves against any significant pressure head. But in a gerotor pump of the type having a check valve in the pump outlet to prevent backflow from the engine, such vapor pressures continue to build as the motor continues to spin and generate heat. The little fluid that may be introduced through the pump inlet is vaporized to a level where the vapor pressure forces the fuel back out of the inlet.
In the pumping of fuel in a wet motor gerotor pump specific pressure criteria must be complied with to avold excessive pressures in the closed fuel system for obvious reasons. ~ccordingly, a pressure relief valve must be pro-vided. The double function of venting vapor pressures until liquid reaches the vent valve, and relieving fluid pressure in excess of a predetermined limit in gerotor fuel pumps, have heretofore been unknown.
The present invention recognizes the desirability of combining the funct1ons of a vent valve with a pressure relief valve to provide a single low cost valve usable with a gerotor fuel pump, especiall~ a fusl pump of the wet motor type.
According to the present invention therefore there is provided a fuel pump vent-relief valve for venting gases or -- 1 -- ,~9 7~35 vapor under a pressure less than a fluid pressure and reliev-ing said fluid pressure when in excess of a predetermined pressure, said ven-t-relief valve comprising: a ball valve; a tubular valve having a vent passage therethrough adapted to be closed by said ball valve; a body having an inlet passage, an outlet passage, and a valve bore therebetween, said valve bore containing said ball valve and said tubular valve, said tubular valve and said body cooperating to define a relief passage between said inlet passage and said outlet passage;
first biasing means interposed said ball valve and said tubular valve said first biasing means acting to bias said ball valve towards said inlet passage and said tubular valve towards said outlet passage, said ball valve adapted to co-operate with said inlet passage to establish a vapor bypass passage therebetween when said ball valve contacts said inlet passage, and said tubular valve having a vent passage there-through adapted to be closed by said ball valve; and second biasing means interposed said tubular valve and said outlet passage, said second biasing means for biasing said tubular valve towards said inlet passage to close said relief passage between said inlet passage and said outlet passage, whereby, said vapor pressure is vented through said vapor bypass pas-sage and said vent passage of said tubular valve until said fuel pump develops said fluid pressure overcoming said first biasing means to cause said ball valve to close said vent passage and whereby fluid pressure is relieved when said relief passage is opened when said fluid pressure exceeds a predetermined relief pressure to urge said tubular valve to-wards said outlet passage to open said relief passage.
Suitably said tubular valve encircles said ball valve. Pre-ferably said tubular valve comprises an axially extending rib means having slots therebetween establishing said relief ~ t~ 3~?

passage. More preferably said inlet passage is encircled by a non-circular seat and said ball valve comprises a ball estab-lishing said vapor bypass passage therebetween. Desirably said non-circular valve seat is square. Suitably said non-circular valve seat is an oblong having a width equal to the diameter of said inlet passage and a length in excess thereof.
Desirably said first biasing means comprises gravitational means cooperating with a preferred orientation of said valve axis being in proximity to the vertical axis with regard to the earth.
Thus, in accordance with the present invention, a vent-relief valve is provided for venting trapped gases or vapor from a fuel pump and relieving the fluid pressure when in excess of a predetermined relief pressure. The vent-relief valve includes a ball valve, a tubular valve having a vent passage therethrough encircling the ball valve and adapted to be closed thereby, and a valve body having an inlet passage, an outlet passage, and a valve bore therebetween containing both the ball valve and the tubular valve. The tubular valve and the valve body define a normally closed relief passage between the inlet passage and the outlet passage. A first spring interposed between the ball valve and the tubular valve biases the ball valve towards the inlet passage and the tubular valve towards the outlet passage. The ball valve is adapted to cooperate with the inlet passage to establish a permanently ope~ vapor bypass passage, by the use of an imperfect seat therebetween even when the ball valve contacts the inlet passage. The tubular valve has a vent passage therethrough adapted to be closed by the ball valve. ~ second spring interposed between the tubular valve and the outlet passage biases the tubular valve towards the inlet passage to normally close the rel~ef passage. The vapor preSsure is ven-ted through -the bypass passage and the vent passage until the fluid pressure overcomes the first spring to move the ball valve to close the vent passage. The fluid pressure is relie-ved when the relief passage is opened by a predetermined fluid pressure to move the tubular valve towards -the outlet passage.
In one embodiment of the present invention a ven-t relief valve for a pump adapted to pump a fluid capable of developing a vapor pressure, said pump further adapted to operate under a starting condition wherein said vapor pressure is less than a fluid pressure and also under a pump condition wherein said fluid pressure is intermediate said vapor pres-sure and a relief pressure, said vent-relief valve comprising:
valve body means having an inlet passage, an outlet passage, and a valve bore means extending therebetween along a valve axis, said valve bore means having an inlet end encircli.ng said inlet passage and an outlet end encircling said outlet passage, said valve body means further having a first valve seal surface at said inlet end and a valve stop surface at said outlet end; a first and a second valve means contained in said valve bore means and movable therein along said valve axis, said first valve means being movable between said inlet and said second valve means, and said second valve means being movable between said first valve seal surface and said valve stop surface; said first valve means adapted to cooperated with a first seat means encircling said inlet passage to establish a vapor bypass passage therebetween when said first valve means seats on sald first seat means; said second valve means having a roof portion, a vent passage therethrough for venting vapors communicated through said bypass passage, and a second valve seal surface encircling said vent passage, said first valve means adapted to cooperate with said second seal surface to effect a first seal therewith; said second valve 7~3~

means further comprising a third valve seal surface encirc-ling said first valve means and adapted to cooperate,d wi-th said first valve seal surface to establish a second seal, said second valve means and said valve means bore establishing a normally closed relief passage therebetween from said second seal to said outlet passage; first biasing means interposed said first and second valve means and applying a first seating bias therebetween adapted to establish said first valve seal until said fluid pressure is obtained, said fluid pressure then overcoming said first seating bias to move said first valve means against said second valve means to close said vent passage; and second biasing means interposed said valve body and said second valve means and applying a second seating bias therebetween to normally establish said second seal until said fluid pressure attains a predetermined relief pressure, said fluid pressure then overcoming said second seating bias to move said second valve means toward said valve stop surface to open said first seal and relieve said fluid pressure through said inlet passage and said relief passage; whereby said first and second valve means cooperate to vent said vapor pressure ~0 until said fluid pressure causes said first valve means to close ~aid vent passage and to normally close said relief passage until said fluid pressùre reaches said predetermined relief pressure. Suitably said first biasing means comprises gravitational means cooperating with a preferred orientation of said valve axis being in proximity to the vertical axis with regard to the earth.
Therefore the present invention provides an improved wet motor pump.
The present invention also provides a fuel pump of the foregoing type having~ a combined vent-relief valve.
The present invention again provides a fuel pump of - 4a -~"~ 71~:3~5 the foregoing -type wherein -the vent relief valve includes two valve members that cooperate with each other in the same valve bore.
The present invention further provides a vent-relief valve of the foregoing ~ype wherein the first valve member seats on an imperfect valve seat and establishes therebetween a vent bypass passage, the first valve member being moved to close a vent passage provided through the second member when the pressure in the pump exceeds a fluid pre,ssure.
The present invention again provides a vent-relief valve of the foregoing type wherein the second valve member establishes a normally clos~d relief passage with the valve bore and is moved to open the relief passage when tha fluid pressure reaches a predetermined limit.
The present invention will be further illustrated by way of the accompanying drawings whereln:-Figure 1 is an end view of one embodiment of a wetmotor gerotor fuel pump having certain features provided in accordance with the present inven-tion;
~ igure 2 is an axial cross-sectional view of the gerotor fuel pump of Figure 1 taken along line 2-2 thereof;
Figure 3 is a transverse radial cross-sectional view of the gerotor fuel pump of Figure 2 taken along line 3-3 thereof;
Figure 4 is a transverse radial cross-sectional view of the gerotor fuel pump of Figure 2 taken along line 4-~thereof;
Figure 5 is an enlarged and exaggerated view of portions of an armature shaft and inner gerotor pump gear;

~ - ~b -, .. ..

3~

F~gure 6 ts a cross-sectional vlew of the outlet houslng w~-th an outlet check valve and vent valve of the gerotor fuel pump of Ftgure 1 taken along llne ~-6 thereof;

Flgure 6A is a cross-~ect~onal v1ew of an 1mperfect valve seat and ball valYe of the vent valve of Flgure 6 taken along 11ne 6A-5A thereof, Ftgure 7 ls a vlew of the gerotor fuel pump of Ftgure 2 taken along llne 7-7 thereof;

Ftgure B ts a fragmentary plan vlew of a portlon of Flgure 2 show1ng the orlentation of the outlet hous~ng by the use of an tndex~ng tab postt~oned bet~een the two motor magnets;

Flgure ~ is an exploded vie~i~in perspective~ of the gerotor fuel pump shown tn Ftyures 1 through 8;

Flgure 9A ls a perspect1ve v~ew of the coupllng arrangement of the armature shaft dn~ the lnner gerotor pump gear of Flgures 1 througll 9;
o~
Flgure 9B 1s a perspective view of 3~ R7~e less preferable a1ternatlve embodiment of the keeper of Figures 7 and 9;

F~gure 10 ~s a partlal sect~onal vte~ of a port10n of an alter-nat~ve outlet houslng, showlng a vent-rellef valve and a bushtng for rota-tably support~ng an end portlon of the armature shaft, . F19ure 10A ls a perspect~ve vlew of portton~ of an alternate ver-s~on of the support bushing and outlet houslng of F19ure 10 show~ng the slot and kcy arrangement thereof for ltmttlng ctrcumferent1al rotat10n of the bushing;

-Flgure 11 ~s a perspective vlew of a psp-off valve of the vent-rellef valve shown 1n Flgure 10;

l~L~ 3351 F~QUre 12 1S a top v~ew of the alternate outlet houslng of F1gure 1~;

Flgure 13 ~s a bottom view of the lnternal conf~gurat~on of the alternate out7et housing of F~gure 12;

F1gure 14 is a cross-sect~onal view through just the alternate outlet hous~ng of F1gures 10~ 12, and 13 taken along line 14-14 of Flgure 12;

F~gure 15 is a vlew taken through just the outlet houslng of F1gures lO, 12~ 13, and 14 taken alon~ 11ne 15-15 of Flgure 1~; and lO . Flgure 16 ls an explod~d v1ew in perspect~ve of certa~n features of the alternate outlet housing assembly, certaln parts thereof belng broken away.

Wlth referencP now pr~marily to F~gures 2 and 9, there ls shown a wet motor gerotor p~mp asse~bly or pump 10 for recelving a fluid such as fuel from a source such as 2 fuel tank (not sho~:n) and dellver~ng pressur1~ed flu1d to a ut11~at~on ~evice such as an lnternal combust~on eng1ne ~not shown). The wet motor gerotor pump assembly or pu~p 10 includes a tubular stepped case 12 generally enclos~ng an ~nlet and pump hous1ng 14, algerotor pump assembly 16~ a motor ~lux r;ng 17, a pump outlet or port and be~ng sealed aga1nst an outlet hous1ng 18 wlth an electrlc motor assembly 20 supported between the lnlet an~ pump houslng 14 and the outlet hous1ng 18.

The tu~ular stepped case 12 termlnates at one end 1n a seal~ng l~p 22 flanged lnwardly to seal agalnst an outwardly extend1ng annular shoulder 24 of the outl~t hous1ng 18. Towards ~ts other end~ the tubular stepped case 12 ~ncludes an outer bore 26 generally def~n1ng a motor chamber 28~ a 7~35 pump bore 30 optionally ~ pped ~nwardly :Erc~n the outer kore 26 a-t ~n a~ lar sho~llder 32 and generally def~nln~ a pump chdmber 34, and an ~nlet bore 36 stepped 1nwardly fro~ both the outer and pump bores 2~ and 30 and generally defin1ng an fnlet chamber 38. The ~nlet.cham~er 38 i~ a~apted to be communlcated 1n a known manner with a fuel source (not shown) such as by a known fluid coupl~ng, condult and ~11ter (not shown).

Made of a one-p~ece d~ecast z1nc structure, the ~nlet ~nd pump hous1ng 14 has a cyllndrlcal outer periphery 40 fitted ~nto the pump bore ~n the pump chamber 34 of the tubular stepped case 12. At an ~nlet end thereof, the lnlet and pump housing 14 termlnates ~n a tubular hub 42 protruding ~nto the ~nlet bore 3~ and inl~t chamber 38 of the tubular stepped case 12 and also has a stepped bore 44 of a structure and function to be descrlbed in greater detail hereinafter. The cyllndr~cal exterlor 45 of the tubular hub 42 ~s separated by an annular space ~6 from an enc1rcling annular sprlng washer 48 hav~ng an inner diameter port~on 50 seated agalnst an annular hub seat 52 protrudlng axially inwardly from the 1nterlor of the tubular stepped case 12. The annular sprlny washer 48 also has an outer dtameter portton 54 captured axlal7y and radlally ~n an annular counterbore 56 formed on the lnlet s~de 5B of the inlet and pump houslng 14 ~ust 1nboard of the cylindrical outer perlphery 40 thereof.

Th~ electr1c motor assembly 20 includes an armature shaft 60 havlng an armature shaft lnlet end 62 and an arm~ture shaft outlet end 64, each shaft end belng rot~tably supported by a respect1Ye tubular bushlng or bearlng 66 and 68 sl~p-f1tted thereon and res11~ently supported by 0-rlnys 70 and 72~respectlYely~engag1ng a bore 74 ~n the lnlet and pump hous~ng 14 and ~ bore 76 1n the outlet hous~ng 1~. The tubular bushlng 66 15 lubr1-cated and cooled by fuel in the ln1et chamh~r 38, and the tubular bush1ng 68 ls lubr~cated by flu~d fed through ax1al slots 75 sp~ce~ about the per1phery of the bore 74. The armature sha~t 60 ls posit~oned generally t7~335 along a central floh axis ~8 through -the wet motor gerotor pump assembly 10 and ls posit;oned therealong by a thrust ~ash~r lS2 belng actively against the thrust washer seat 184 ~h~ct~ is part of th~ pump ~ou-tlet or p~rt plate 180 by means of tlle m~gnetic attraction acting t~ttwe~n the magnets 240 an~ ~42 and the arma-ture stack. The bearing 66 of the inlet is positioned by me~ns of a shoulder 80 extend~ng outwardly from the tubul.lr bushing 6~ and an annular shoulder 82 extending 1nwardly from the tubular hub l~2 to thereby capture the 0-r~ng 70 therebetween.

Adapted to rotate ~n the motor chamber 28, the electrlc motor assembly 20 includes an armature ~ made of a plural~ty of ar~ature windings 36 wound through a plural~ty of slotted armature laminat~ons ~not shown) press f~tted on a knurled portion (not sho~!n) of the armature shaft 60. Each armature winding 86 has respectlve flrst ~nd sec.ond ends term1nated 1n a known manner at a co~nnutator ~8 a~apte~ to electrically and sl~dlngly engage a pa1r of d1ametr~cally opposed commutator brushes 90 and ~2 electrlcally coupled to respectlve cup-shaped ter~nals 91 and 93. The ~rushes ~0 and 92 are urged agalnst the commutator 8~ along d brush d1splacement axis 94 by a respective f1rst and second brush spring 9fi ancl ~8.

Press f~tted on the knurled portlon of the armature shaft 60 ax~ally outboard the oppos1te ~nds of the armature laminatlons are a f1rst and a se~ond end ftber 100 and 102, each havlng elght fingers 104 extending rad~ally outwards from a fibrous central tubular hub 106 spaced equlangu-larly thereabout, each flnger 104 having at its tlp an axlally extending tab 108 extend1ng ax1ally inwards towards the armature lam~nat1cns to provlde a ?~ stand o~f therefrom. The outward ax~al si~e of each f~nger 104 has a smooth curved outer surface therealong so as to non-abras~vely engage and support the end loops of the armature w~ndings ~6. The flbrous central tubular hub 106 of the end ftber 102 has an annular thrllst shoulder 110 extend1ng radlally out~ards ~herefrom and terminates ax~ally in a pair of dr~ tangs or dogs 112 and 114, best seen in Figure 9, in the form of dla~e-trically-opposed arcuate sectlons extending axlally towards and lnto the inlet and pump housin~

As may be better understood with reference to Flgures 2, 3, and g, the inlet and pump houslng l~ has a counterbore il6 opening towards the armature 84 and definlng a gerotor cavity 118 and also has a central Dore 120 therethrough. The counterbore llG, the gerotor cavi ty 118, and the central bore 120 are concentric about an offset axis 1~2, best seen ln ~lgures 3 and 9, hav~ng a predetermined radial offset 124 from the central ld flow axis 78 along a f~rst radial direction generally perpendicular to th brush displacement axls 94. As may be better understood w~th reference to Figures 2~ 4, and 9, an oblong (lepresslon 1~6 and an oblong aperture 128 are prov1ded in a bottom surface 130 of the counterbore llfi and are dlsposed generally concentrlcally about the central bore 120. As best seen ln Ftgure C~ ~3i~
4, the inlet s1de 5& of the inlet and pump nousing 14ihas 2~-oblong inlet depresslon 132 extending axlally there~n. At first the oblon~ inlet depression 132 on the inlet slde 58 col~nunlcates with thè oblong aperture 128 in the bottom sur~ace l30 of the counterbore li~ and a second oblong inlet depresslon l36 on the ~nlet s1de 5a of the inlet an~ pump hous~ng 14 which also ~ ~ ~h~
communicates wlth the entire ohlong aperture 12~ ~n the bottom ~ 13~.
~he flrst and second inlet depressions l3~ and 136 cooperate to proY1de unpressurized fluid to the gerotor cavlty 118 tor hoth prlmlng the gerotor pump assembly lfi and provid~ng fluid to ~e pressur1zed thereby.

Located in the gerotor cavlt~ 118 of the gerotor pump assembly 16 ar~ an ~nner pump gear 142 and ~n outer pump gear 144, shown only in Flgure 3~ Th~ 1nner and outer pump gears 142 and 144 have re$pectlve serles of inner and outer pu~p teeth 154 and 156 and pump teeth spaces 158 and 160 1ntervening therebetween. The inner pump teeth 154 o~ the ~nner pump gear 142 ~e~ng formed to pumplng1y seal an~ engage the outer pump teeth 156 and _~J_ 3~35 teeth spaces of the outar pump gear 1~9 while the outer pump teeth 156 of ~he outer pump gear 144 are for~ed to pumDingly seal and engage the ~nner pump teeth 154 and the t~eth spaces 1~ of t~le Inner punlp ~ear 1~2. The outer pump gear 144 has a cylindr~cal external perlphery 1~2 that 1s sllp-fitt~ngly rece~ved by and posltione~ ln the counterbore 1lb of the gerotor cavlty 118. The ~nner pump gear 142 has a central ~ore 164 therethrough whlch~ as may be better understood ~lith reference to F~gures 2 and 5, has a tapered openlng 166 faclng the bottom surface 130 of the c~unterbore 116 of the inlet and pump housing 14. The ~nternal d~ameter of the inner gear c~ntral bore 164 is slightly greater (e.g., O.Q01 inches) than the external dia~eter of the armature sh~ft 60 pass~ng ther~throu~h and the axi~l length of the lnner gear central bore 164 is selected bo be comparatively short ~e.g., 0.005 inches) w~th respect tn the internal diameter th~reof sn as to allo~ the armature shaft 60 to p~vot sl~ghtly end-to-end rela~ive to ~he lnner gear cen-tral bore 164 1~ and thereby allow the 0-ring 70 to sel~align ~he ~rmatur~ shaft lnlet end 62 in the bore 74 of the tub~llar hu~ 42. Such self-aligning allows the armature shaft 60 to eff ect small angles with respect to the central flow axis 78, such angles increas~ng wlth increasing n~anufacturing and assembllng toler~nces.

?0 Whlle thus allowed to ~elf-al19n relat~Ye to the lnner pu~p gear 1429 the armature shaft 60, as t)etter seen in Flgures 3 and 9A, nevertheless dr~ves the 1nner pu~p gear 142. The 1nner pump year 142 has a palr of dr~-ven tangs or dogs 172 an~ 174 e~ter,din~ radlally ~nwards therefrom into the drtve coupl1ng cav1ty 170. Form1ng a drlYe coupllng 177, as best seen ~n Figures 3 and ~A, each of the drlve tangs 112 and 114 have an ~ncluded angle of approximately one hundred and eighteen degrees (118), and each of the dr1Yen tangs 172 and 174 have ~.n ~ncluded angle of abou~ fi~ty-elght degrees (~8). The four tangs 112, 114, 172 and 174 thereby hav~ng a total clrcu~-ferentlal clearance of approx~mately e~ght ~egrees (~). Such clearance allows suff1c~ent c1rcum~erentlal play to perm~t easy assembly of the dr~ve 7~;~S

coupling but ~l-t sl~ght axial ~isalignn-ent thereof to allo~Y the end--for-end self-al7ynment of the armature shaft GO relat7v~ to tlle inner pump ~ear 142.

Complet7ns the g~rotor pump asser,lbly 16 are an annular pu~p outlet or port pla-te 180 and a thrust washer 182 made of Teflon loaded Ultem. The pump outlet plate 180 has an annlllar tllrust surface 1~4 counterbored lnto the outlet side 186 thereof and a bore 18~ thorethrol)gh of a tlla~eter suf-ficient to allow th~ drive tangs 112 and 114 of tlle fibrous central tubular hub 106 to freely pass therethroush h'ith a suitable clearance (e.g., 0.00~
1nches). The pump outlet plate 180 also has 2 cyl7ndrical outer perlphery 190 and an annular radial groove 192 extenaing lnboard therefrom, the annular outer peripheral surface 1SO belny rece1Yed in the outer bore 2G of the tubular stepped case 12 and be~ng seated against th~ face of the annular shoulder 32 there1n, prov~ding both radial and axial positioning relative to the motor flux ring 17. The thrust washer 182 is pressed against the annular thrust sur-face 184 of the pump outlet plate 180 by the annular thrust shoulder 110 of the f1brous centr~l tubular hub 106. T~le thrust washer 182 has a pair of dlametr~cally-oppose~ arcuate tangs or uogs 133a and 193b extend1ng radlally inward to engage and be dri~en ~y the dogs 112 and 114 of the f1brous central tubular hub 106.

On an axial s1de faclny the inner and outer pump gears 142 and 144~ the pump outlet plate 180 also has an ohlong depress10n lg6 and outer aperture generally match~n~. the shape ~nd pos~t~on of the oblon~ depress10n 126 and the oblong aperture 128 ~n the bottom surface 130 of the counterbore 11G of the gerotor caY1ty 118 of ~he inlet end pump hous~ng 14. To afford proper pump pr~m1ny and other des1rable pumping characteristlcs, the oblong aper-ture 128 and the oblong depression lS6 are com~unlcated through, respect7vely, bores 120 and 188 bv appropr7ate rad7al slots 200 and 202, as best seen 7n F1gures 2 and ~. Moreover, to prov7de a suitable outlet port for flu~d pumped to a f~u1d pressur~ in tl-e ~erotor cavity 118, the annular pu~,p outlet p1ate 1~0 has the oblong outlet aperture 198 formed therethrough and posi-1 ~ q ~
t~oned and shaped to correspond hlth the oblong depress~on 126. To properly positlon the pump outlet plate 1~0 circumferentlally ~lith respect to the inlet and pump housing 14, a palr of locator pins 204 and 206 are aff~xed thereto to extend ax~ally from an annular r~dial surface 20B to engage suitable holes 205 and 207 through an anrlular rad~al surface 209 of the pump outlet plate.

Pressure flutd from the oblon~ outlet aperture 198 of the pump outlet plate 180 ~s ~ulded therefrom and protected from the w~ndage effects of the armature ~4 by a tunnel and magnet keeper device 210, best seèn ~n F~gures 7 and 9. The tunnel and magne~ keeper deYice 210 conslsts of a f~rst flow channel or passage 211 shlelded from the anmature ~indage t~xtend~ng substan-t~ally the entire axlal length of the motor chamb~r 28 between th~ pump outlet plate 18n and the annular shoulder 24 of the outlet housing 18.
Shaped generally ~n the form o~ an invert~d staple, the tunnel and magnet keeper dev~ce 210 has a central br~dge port~on 212 ~ounded by a pair of leg port~ons 214 and 21~. The central hridge portion 212 has a sl~ghtly convex shape, as seen from a po1nt external to the pump, to match the clrcular con-tour t)f the periphery of the ar~ture ~4, and the pa1r of leg port~ons 214 flnd 216 extend radially outwards from the central bri~ge port10n 212 to seat Dn an inner peripheral surface 218 of the cylindrical magnetic m~tDr flux rtng 17. The flux rlng 17 also extends substant~ally the entire ax~al length b~tween the pump outlet plate 180 and thc outwardly extendlng annular shoultler 24 of the outlet hous1ng 18.

To allow suhstantially un~mpeded flcw of pressure flu~d ~rom the oblong outlet aperture 198 into the tunnel and magnet keeper deY~ce 210 whlle also imparting a des~red clrcumferent~dl posltion to this devicP, the lnlet end 222 thereof 1s provlded with two ax~lly extendin~ protrus~ons 224 and 226 spaced rad1ally apart to proYlde a flu1d entrance 22B therebetween. The axial protrus10n 224 te~inates in a butt end 230 abutting d~rectly agalnst the annular radlal surface 2~ of the pump outlet plate 180. The ax~al ~d'~ 3~
protruslon 226 termlnates ln a stepped tab 232 hav~ng a butt end 232a abutting agalnst thP c~lular radial surface 209 and a pin portion 232b e~Ytending ~nto the outlet slde o~ the hole 207 provlded to properly orlent the pump outlet plate I80 wl-th the lnlet and pump housing 14 as aforementioned, The leg port~ons 2I4 and 21~, of the tunnel and magnet keeper devlce 210 cooperate ~lth a pair of tabs 234 and 236 extending circumferen-tially outwards from the respective axlal protruslons 224 and 226 to pro-perly position the palr of crescent shaped motor magnets 2~0 and 242 bot c~rcumferentially and ax~ally wlth respect to the armature B4, As may be I0 better understood wlth reference to F19ures 7, 8 and 9, each crescent shaped motor magnet 240 and 242 ls bounded along its axlal length by a first and a second set of juxtaposed ax1al sur,aces 240a, 240~, 242a and 242b, and each motor magnet 240 and 242 ts bounded at its inlet ard outle$ ends by respec-tlve end surfaces 240c~ 242c, 240d ~nd 242d.

In assembly, the tunnel and magnet keeper dev~ce 210 is flrst inserted s~ that th~ pin portion 232b thereof is positioned ln the locator hole 207 of the pump outlet plate 180. Thereafter, the crescent-shaped motor magnets 240 and 242 are ~nserted so that the 2xial surfaces ~40a ~nd 242a respectlvel~ abut tne leg port~ons 214 and 2I6 ~nd the end 0 surfaces 240c and 242c abut the tahs 2~4 and 236. lo properly space the motor magnets 240 and 242 fr~l the outlet port plate 180 and prov1de a second axial channel 211a therebetween, a Y-shaped compress1On sprlng 246 ls then lnserted between the second set of ~uxtaposed axlal surfaces 240b and 242b to urge the axlal surfaces 240a and 242a clrcumferentlally into abutt~ng cont~ct w1th the leg portlons 214 and 21~. of th~ ltunnel and magnet keeper device 210.

F1nally, the outlet housing 18 ls lnserted ~nto the tubular stepped case 12. The clrcumRerential or~entation of the outlet hous~ng 18 h~ing determlned relative to the tunnel and magent keeper devlce 210, as 3~ best seen ln Flgure 8~ by an arcuate tab 2~8 extend1llg between the ax~al 793~
surfaces 240b antl 2~2b of the cres-ent s~aped motor magnets 240 and 242. A
pump out1et port or fitting 252 th.rough the outlet housing 1, is thereby aligned alon~ the same ax~al plane ~nters~ct~n~ -the center of the tunnel and magn~t keeper devlce 210 an~ the center of the olltlet aperture 1~8 through the pump outlet plate 1~0.

The forego~ng proper circumferential or~entat~on of the outlet ~ouslng 18 relat1vP to the tunne~.and magnet kceper deY~ce 21Q permits a flow of pressurized fluid smcothly there~hrough directly from the outlet aper-ture 198, through the first f10~l passa~e 211~ to the pump outlet port 252 of the outlet housin~ 1$~

It has been found throu~h experimental test results, under stan-dard condit10ns, that the foregoin~ apparatus substant~ally improves pump performance. Comp~red with wet pumps of slm~lar sk e and capacity, the foregoing wet motor pump assembly provided the des~red fluid pressure at lS substantlally 1ncreased flow rates wlth substantlally decreased armature currents. For example, ln one typical appl~cat10n to a conventlonal passenger car lnternal combust~on engine, flow rates were un~formly ~ncreased by at least three gallons per hour wh~le the corresponding arma-ture currents were decreased at least twelve percent (12~).

Some portion of th1s improvement 1s attr1buted to merely provld~ng the axlal ~1NW channel, such as $he magnet keeper 210a of the type shown ln Flgure 9B. Such ~ keeper has a central bridqe portion 212a abutting radially outwards aga~nst the flux rln~ 17 and bounded by a pa1r of leg por-tions 214d and 216a open~ng radially ~nwards towards the armature 84.
However, such a keeper would ~llow the armature windage to ~nduce radlally oriented hydraul~c curls ~n the flo~ channels 211~o 8ut such turbulence would reduce the effective cross-sect~onal area of the axial flow channel 211b to a small portion of the ~ctual cross-sectioned area thereof. To avoid su~h curls and turbulenc:e and substantially lncrease the effect~Ye area, the tunnel and magnet keeper dev~ce 210 of the preferred embodlment ~4~3~

1s prov1ded so that the central br1tlge portlon 212 thereof sh1elds the flow therethrough from the armdture wlnda~e. Sllould fllrther 1mprovements be des~red to avo1d hydraulic curls indlJced ~1th an or1entatlon ln the channel 211 by the flow restr1ct10n 1mposetl by the circumferential width thereof the channel 211 could be further subdiv1ded into subchannels of a plurality of tubes or slots. Such subchannels ~oul~ proYi(le a laminar flow substan-t1ally 1ncreas~ng the effective cross-sect10nal area of the tlow to the actual cross-sectional area of the challnel.

As hest seen in Figures 1 and 6 the outlet housing 1~ made of 2 molded plast1c such as Ultem inclu~!es the pu~p outlet valve 250 with the t~bu--lar outlet port or fitting 252 adapted to be ooupled to an internal co~busticn engine. The tubular outlet fittin~ 2i~ has an internal outlet passage 251 hith a slotted seal 2~3 fitted Intr! ar~ outlet bore 254 to enclose a ball valve 2~5 of a one-way check valve ~5fi therein. The outlet hous~ng l~ pro-vides an annular seat 257 cooperating ~ith the ball valve 255 to provlde the one-way check valve 256 preventing L~ackflow from the engine into the pump. To allow normal flow from the pump 10 to the eng1ne9 t~e tubular outlet ~1tt1ng 252 termlnates 1n four tapered prongs 25~ forming slots 259 therebetween the tapered prongs 258 normally restra1nlng the outward move-ment of the ball valve 255 and the slots 259 allow1ng the fuel to flow out therebetween. The angle formed by the tapered pron~s 25 1s such as to cradle the ~all valve 255 so as t~ prevent oscillat~on of the ball at cer-taln flow rates.

A further feature of the ~et ~otor pump asse~l)ly is a vapor vent valve 260 prov1ded in the outlet hous1ng 1~ as best seen 1n F19ures 6 and 6A. The vapor vent valve 260 1s locate~ diametrically opposlte the 2i outlet valve 250, and 1ncludes a ball 2~2 enclosed in a valve bore 264 by a tu~ular vent f1tt1ng 2~6 having a vent passage 268 therethrough and having ; an annular hub 270 seated aga~nst an annular seat1ng surface 272 of the 1~'7~33~

outlet housin~ 1~. A helical spring ~7~1 b1ases ehe ball ~G2 d~ay from a shouldor 27fi enclrc~ing an annular lnternal hub 278 of the tubular vent fltting 266 and towards an imperf~ct seal in th~ form of a square seat 280, best seen in Fi~ure ~A, at the end of a vent ~ore 282 formed in the outlet hous~ng 18, l~hen ~n contact ~it!l ti~e square ~o~t 2~0, t!le l~all 262 touches the square seat 280 at only four points 2~4a, 2~4b, 2.~4c, and 2~4d, such arrangement provi~ng four suitable bypass passages 286a, 2~6b, 28~c, and 286d. Wlth thls arrangement, a vapor pressure developed by the ~erotnr pump assembly 16, especlally dur~ng self-priming thereof, is unloaded through the bypass passages 28fia, 286b, 286c, and 2~6d unt11 liquid reaches the output slde of the pumping elements and the vent bore 282. Thereafter, the fluid pressure on the ball 2~2 w~ll overcorne the bias thereon by the helical spring 274 to seat the ball 262 on the annular ~nternal hub ~7~ formed at the ~nboard end of the tubular vent fitting 265, thereb~Y closing the vent passage 268 and allowing normal pumping operat~on an~ outlet througll the outlet port 252.

The square seat 280 in the foregoing vapor vent valve 250 may be replaced by other sultable non-circular, or imperfect, valve seats lncluding, for example, part1ally-circular vdlve seats as mlght be effected by a clr-cular valve seat havlng axlally extending slots therethrough.

A further appl1cation of an lmDer~ect val~e seat is 1n comb1nation w1th a vent-rel~ef valve 290 sho~:n molded lnto the alternate outlet houslng 19 ~n F1gures 10 and 11. As may be better understood with reference thereto, a hall 292 ls enclosed ~n a bore 2~4 provided ln the outlet hous~ng 19, the bore 294 defln~ng therein a valve cham~er 2~5. One end of the bore 294 ~s in constant communlcat10n wl~h a vent-relief passage 2g6 prov1ded through the end o~ the outlet^housing 1~, and the other end of the bore 294 ls suitably seeured, such as by ultrasonic welds9 to a ~alve seat member 298 hav~ng a central passage 300 therethrough~ln constant cornmunicat~on w~th the motor chamber 28. The centrl~l passage 300 opens 1nto an oblong valve seat -lfi -~f~L~ S

~01 ln the form of an obton~ col!nterbore hay-i~ri a wldth equal to the d~ameter of thc c.entral passa~e 30~ ~nd a lengtll twice thereof. When in contact with the valve seat m~mber 298, the bk~ll 292 can contact the oblong valve seat 301 elth~r at t~Jn dlarnetr~cally opposite points ~f central~y located thereon~ or ln ~ seml-circle linQ contact if shifted to elther ~xtreme slde thereof. Elther way~ th~re ls ~ hyp2ss p~saq~ constantly open between the ~all 292 and the oblon~ valve seat 3n~.

Also located ln the valvP chamb~r 2~5 formed by the bore 2g4 and the valve seat ~ember 29~ ls a tubular pop-~f~ or relief valve 302, 2 first hel~cal sprlng 3Q4, a second helical spring 3~fi, and an O-ring 30~. One end of the first helical spring 304 is biased against an annular shoulder 310 formed 1n the vent-relie~ passag~ 2~6, a~d t~e ~ r end of t~l~ first helical spring 304 is biased aga1nst an annular top surface ~12 formed at the top of the pop-off valve 302 and encircllng a centrcil vent passage 314 therethrough, The hel~cal spring 304 blases the tubular pop-off valve 302 ~o nor~ally se~t and seal a~a~nst the O-ring ~0~ the O-ring 30~ being normally seated on an dnnular seat surface ~16 provlded ~n the valve seat me~b~r 29~ about the oblong valve seat ~01 thereof. Wh~n the pop-off valve 302 is thus normally urged aga1nst the O-ring 308 to seal against the annular seat surface ~16, a normally=open bypass passage ~s ~stahllshe~ from the central passage 3~0 of the val~e seat ~ember 298, thrDugh the central vent passage 314 of the pop-off valve 3029 and the vent-rel~e~ pdssage 29~ of the outl~t hous~ng 19.
Thls vent bypass passage belng closed as wlll be descrlbed when the pump assembly 10 produces a flu~d pressure ln excess of a predetermlned maxlmum ; 25 ventlng pressure in the fonm of a liquid at the l,all 292.

The tubuiar pop-off valve 3C2 also has an externally slotted tubu-lar portlon 318 hav~ng a tube bore 320, at one end clear~ng the outer diameter of the ball 292 and havlng an annular hub seat 322 dependlng inter-nally from the other ~nd. One end of the second hellcal spring 306 ~s 3G seated about the annular hub seat 322, and the other end engages ~

peripheral surf~ce of the hall 2~2 to normally urge the ball 2~2 to seat on the ohlong valve seat 301~ llow~ver, l~hen the fluld pressure exper1enced by the pump 10 exceeds the max~muin vont~ng pressure, such excess pressure over-comes the bias of the second helical sprin~ 305 on the ball 292 and r,'oves the ball ~92 towards the annular hll~ seat 3~2, seat~n~ on the same when the pump pressure exceeds the predetermlned maxlmum venting pressure. At pump pressures bet~een the maximum vent~ng pressure and a predeterm~ned relief pressure, the ball 292 closes the flu~ rassa~e het~een the central seat_ passage 300 and the vent-rel1ef passa~e 2~lfi.

To provide a rel~ef capab~lity or condit10n ~Ihen the pump experiences a fluid pressure ln excess of thc pred~termined rell~f pr~ssure, the axial ~eriphery ~24 of the pop-off valve ~02 ~s prov1ded with six ribs ~26a9 3~6b, 326c, 32fid9 32fie, an~ 3?6f, extending radially outwards ana spaced equlangularly thereabout on the tube pnrt~on 318, the r~bs 326a through 326~ also gu~d~ng and centrally pos~tionirlg the pop-n~f valve 302 with respect to the bore 2g4. Eacll of the axial ribs 326a through 326f ~5 cDntiguous with a respect~ve spar~r tab 328a through 328f upstand~ng a~lally from and about the annular top surfac~ ~12 and ~hecentral vent passage 314 therethrough. The tabs 32~3athrQush 32~f are a~apted to abut a~a~nst and space the rema~nder of the pop-off valve 302 ax~ally from an annular stop surface 330 counterbored ln the outlet housin~ 1~ about the vent-relief passage 296. The ribs 326a throu~l- 326f a~d the respect~ve tabs 328a through 328f form passages or slots 332e through 332f ~herehetween spaced equiangul~rly about the central periphery 324 of the opc~off valve 302. The slots 332a through 332f cooperate w1th the vent-relief passage 29~ to contlnually commun~cate the ent1re sp~ce b~tween the ~ore 294 and the axial periphery 324 ofthe pop-off valve 302 wlth the vent-re?ief passa~e 2~6. I~owever, t~lls space ~s not commun~cated wlth the central passa~e 30~ until the pump exper~ences a fluld pressure ln excess of the relief pressure, such excess pressure then overcomlng the seat~ng b1as of thc- first helical spring 304 against the C-ring 308 ~'7~3~3~

t~ ~her~by rlove the ~op-of~ valve 30~ ~Yay from tlle annular seat surFace 316 an(l t~lar~s the annlllar stop surface 330. ~uc!l excess punlp pressure thereby .
ur~es thePoP-off valve away from the O-ring 308 to unseat from the annular seat sur-face 316 thereby openin~ a passage through the slots 33~a tl~rough 332f frcm ~he c~-tral passage 300, between the bore 294, -the aYial peripllery of ~le rop-off val~e 302 through the slots 33?a tllrou~h 33Lf and out through the vent-relief passage 2g6.

Further alternate features of the pump 10 as sllr)wn ln Figures 10 and lOA are alternate tubular bushin~s 340 and 340a the axial length of whlch has a convex form or raised portlon ln the shape of an nut~ardly extendin~ bo~l or crown 342 that contacts the bore 344 in the outlet housing 1& to allow a sl~ght erd-for-end self-ali~nment of the armature shaft 60.
To restraln the tubular bushing fro~ rotating in the bore 344 an anti-rotatlon device is prov~ded ~n the fom of d slot an~ key arrangement 348 i5 wherein a slot 3q8a 1n the tubular bushing 340 is circ~nferentially somewhat wider and radlally somewhat deeper than a key 3~8b.

A further feature of thc het ~otor gerotor pump 10 is the util1~a-tion of otherw1se existing structurc in tlle alternate outlet housin~ 19 ln combination wlth addltional passages formed therein to cool and lubr kate a portion oF the tubular bush~ng ~4~ bet~een the point of contact of the ralsed portion 346 ~l~th the bore 344 and the roof 360 of the out1et hous~ng.
As may be better understood with reference to the outl~t housing 19 shown in F1gures 10 through 16 a bearing lubrlcation and coollng system 350 ln the fonm of a flow network 354 1s provlded between a ra~sed cap portion 352 a cylindrical peripheral surfdce 8 of the commutator 88 the ~ore 3~4 and a pa~r of bru-ch support ridges 356 and 358 for support~ng the bru_hes 90 and 92 respectively.

As best seen in Figure 127 the raised cap portion 352 supports the outlet valve 250 and the vent-relief valve 290 hose fittin~, ard includes the _19_ 33~
generally flat roof 360 s~p~orting the outlet port L5(1 and the vent-rellef valve 290 hose fittillg, and furth(?r inclucles 2 pa~r ~f s;de ~alls 3~2 and 364, and a pa~r of curve~ end ~alls ~6 an~l ~fi~.

The fl~ network 354, ~hen vlewed ~n the transverse rad~al plane ` of Figure 13, ~s shaped generally ir. the 'orm of the Roman numeral X. I'~ore particularly, tlle flo~ network ~54 i~cludes ,our ~ranclles 370, 372, 374, and 376, each in the shape of a dog 1~9 and edCh comr.unicating w1th the axial length af the bore 3~,4 as well as an annu1ar recess 376 encircling a stop hub 380 projecting into the bore 3~ fro~ the roof 3~Ø Each of ihe ~ranches 370 through 37G extends ax~ally along the ~)ore 344 to the Inner surface 3~1 of the roof 360. Each includes a c1de wall branch port10n 370a~
372a, 374a, and 376~. Each suc~, ~ide wall hranch port~on is generally parallel to one of the s1de w~lls ~6~ and 3~4, w1th the ~ide ~all branch port~ons 370a and 372a generally spanr.ing the vent-rel~ef valve 2gO whlle the s~de wall branch portlons 374~ and 37~;a genera71y span the outlet port 252. Each of the branches 370, ~72, 374~ and 376 also ~nclude a radtal branch portlon 370b, 372b~ 374b, alld 376b, eac!l term~natin~ in a respect~ve side wall branch portion w~th a respective radial slot 370c, ~72c~ 374c~ and 376c formed c~rcumferent~ally through a bore wall 382 prov~ding the bore 344.

The brush support rldges 35fi and ?.58 include an arcuate r~dge crown or wall element 356a and 358a faclng radially lnward, the arcuate r~dge crown 356a be1ng bounded by a pair of radial r~dge slde walls 35~b and 356c whlle the arcuate ridge crown wall 35~a is ~ounded by a patr of rad~al r~dge s1de ~alls 358b and 358c, Each set of the radial ridge s~de wails 356b, 356c, 358b, and 3S8c are spaced rad~ally apart by an ~ncluded angle of abou~ n~nety degrees (90~ and, together ~lth the1r respectlve arcuate rldge crown walls 356a and 358a~ extend axially to an arcuate ridge wall counter-bore 384 at a depth correspondlng with th~ axial w~dth of the co~ut~tor 88.
The arc~ate rldge crCwns and walls 356a and 3~8a are of a dica~eter slightly '7~3S
greater than that of the cnmmutators ~.8 to allow clearance therebeth~een for ~ppropriate brush con~utator 1nteraction. The bore 344 cor,~nences at the depth of the arcuate rldge counter~ore 384 and extends axially to the ~nner sid~ 361 of the roof 360. W~th the ~ore 344 startlng below lhe brush sup port r,dges 356 and 358, there ~s an arcu~te opening of approximately ninety degrees (90) between the radial ridg~ Side walls of the opposing brush support ridges 356 and 358. In other ~lords9 there is a circumfer~ntial gap of about nlnety degrees (90) extendtng the aYidl l~ngth of the COnTnUtator 88 between the ra~al ridge slde WA1l5 356b and 358b and a similar gap extends circumr ferent~ally between the radial ridge side walls Assum~ng that the armature ~4 is energized to rotate in a coun-terclockw1se dlrection as vle~wed in F~gure 139 the cyl~ndrical periphery of the commutator ~8 viscously drags fluid therew~th, such fluid being plcked up ~y the rotation o~ the con~nutator at the radial slots 376c and 372c havlng, respectlvely, the radial ridge s~de ~alls 3S6c and 35~b and belng delivcred or thrown o~f against tl-~ next radial ridge s1de ~/alls 358c and 356c~ respect1vely, of the radial slots 374c and 370c. The fluid picked up at the diametrlcdlly opposite radial rldge s1de walls 356c and 358b there~ore experiences a h1gher veloc1ty than the flu~d ~m~acting and collectlng at the dl2metrically OppOs~te radial rid~e side walls 356b and 358c. This differenoe in veloeit1es causes the fluld ln the rad~al slots 370c and 374c to move slGwer and therefore be at a pr~ssure hlgher than the fluld at the radial slots 372c and 376c. A similar pressure differential could be effected by other structures such as a vane or other form of flow res~stanee, the rldge walls ~n the present embodi~.ent servin3 a dual func-t1On of support1ng the brushes whlle also prov1d~ng the necessary pressure d1fferent1al.

In any event, the resulting pressure d~fferentlal created by the drag forces of the co~mutator periphery 69 on the flu1d at the indicated rad~al rldge s~de walls effects a pu~plng actlon of fluld ~n the radlal ~ 5 branch port~ons 370b and 374b. Such pumping action i5 axially outwards towards the 1nner surface 361 of the roof, then r~ally inwards into the annular recess 378, then axial1y about the tubular bushing 340, then radially out-wards from the annular recess 378, and finally back through the opposlng radial branch portlons 372b and 37~1b. In other wor~s, the commutator cylindrical peripheral sur~ace 89, the brush supp~rt ridges 356 and 35&, and the flow networ~ 354 establish two parallel pu~p~ng chambers or circuits separated by the co~-- mutator 88 but jo1ned at the annul~r recess 3-/8. The pressure differentials created by the dtfference in velocit~es at the indicated radial rldge side walls provldes two insoming and two outnoins flows of fluid thereat~ both flows combinlng to cool and lubrioate the tuhular bushin~ 340 and the bore 344. With such cool~ng and lubr~cation, the life of the upper tub~lar bushing 340 has been fountl to be signi~cantly increased ov2r the llfe of the same bearlng wlthout such lubrlcation an(l cool~n~ oreover, an acceptable lubrication w~ll al50 occur by provi~in~ st a single c~rcu~t com-munlcattng with the annular recess .~78 con~unicattn~ wtth the llpper end por-tion of the tubular bushing 340 above the point its crcwn 342 contacts the b~re 344.
Such lubr~cat10n woul~ be less than that provided by the dual parallel c1r-cu1t shown. Also, a sl1glt flow c~ fluid mi~ht b~ provi~ed hy such a single ZO circuit should the 1nternal structure by happenstanee provi~e a sufficient pressure different1al betweer the inlet and thc outlet to the annular recess 378, without the benefit of add~t10nal pre S5 llre bu i ld1ng structures.

Although the best mode contemplated l-y the inventor ~or carry~ng out the present 1nventton as of the filtng date hereof has been shown as Z5 described here1n~ it ~llll be ap~arent to those sk~lled in the art that suitable modtficat~ons, variat~ons, and equivalents may be r.lade wtthout departlng from the scope of the tnventlon. Thts tnventlon ~s to be limited solely by the terms o~ the claims a~p~nded t~ereto.

Claims (9)

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

1. A fuel pump vent-relief valve for venting gases or vapor under a pressure less than a fluid pressure and releiving said fluid pressure when in excess of a predetermined pressure, said vent-relief valve comprising:
a ball valve;
a tubular valve having a vent passage therethrough adapted to be closed by said ball valve;
a body having an inlet passage, an outlet passage, and a valve bore therebetween, said valve bore containing said ball valve and said tubular valve, said tubular valve and said body cooperating to define a relief passage between said inlet passage and said outlet passage;
first biasing means interposed said ball valve and said tubu-lar valve said first biasing means acting to bias said ball valve towards said inlet passage and said tubular valve towards said outlet passage, said ball valve adapted to cooperate with said inlet passage to establish a vapor bypass passage therebetween when said ball valve contacts said inlet passage, and said tubular valve having a vent passage therethrough adapted to be closed by said ball valve; and second biasing means interposed said tubular valve and said outlet passage, said second biasing means for biasing said tubular valve towards said inlet passage to close said relief passage between said inlet passage and said outlet passage;

whereby, said vapor pressure is vented through said vapor bypass passage and said vent passage of said tubular valve until said fuel pump develops said fluid pressure overcoming said first biasing means to cause said ball valve to close said vent passage and whereby fluid pressure is relieved when said relief passage is opened when said fluid pressure exceeds a predetermined relief pressure to urge said tubular valve towards said outlet passage to open said relief passage.

2. The vent-relief valve of Claim 1, wherein said tubular valve encircles said ball valve.

3. The vent-relief valve of Claim 2, wherein said tubular valve comprises an axially extending rib means having slots therebetween establishing said relief passage.

4. The vent-relief valve of Claim 3, wherein said inlet passage is encircled by a non-circular seat and said hall valve comprises a ball establishing said vapor bypass passage therebetween.

5. The vent-relief valve of Claim 4, wherein said non-circular valve seat is square.

6. The vent-relief valve of Claim 4, wherein said non-circular valve seat is an oblong having a width equal to the diameter of said inlet passage and a length in excess thereof.

7. The vent-relief valve of Claim 1, wherein said first biasing means comprises gravitational means cooperating with a preferred orientation of said valve axis being in proximity to the vertical axis with regard to the earth.

8. A vent-relief valve for a pump adapted to pump a fluid capable of developing a vapor pressure, said pump further adapted to operate under a starling condition wherein said vapor pressure is less than a fluid pressure and also under a pump condition wherein said fluid pressure is intermediate said vapor pressure and a relief pressure, said vent-relief valve comprising:
valve body means having an inlet passage, an outlet passage, and a valve bore means extending therebetween along a valve axis, said valve bore means having an inlet end encircling said inlet passage and an outlet end encircling said outlet passage, said valve body means further having a first valve seal surface at said inlet end and a valve stop surface at said outlet end;
a first and a second valve means contained in said valve bore means and movable therein along said valve axis, said first valve means being movable between said inlet passage and said second valve means, and said second valve means being movable between said first valve seal surface and said valve stop surface;

said first valve means adapted to cooperate with a first seat means encircling said inlet passage to establish a vapor bypass passage therebetween when said first valve mens seats on said first seat means;

said second valve means having a roof portion, a vent passage therethrough for venting vapors communicated through said bypass passage, and a second valve seal surface encircling said vent passage, said first valve means adapted to cooperate with said second seal surface to effect a first seal therewith; said second valve means further comprising a third valve seal surface encircling said first valve means and adapted to cooperate with said first valve seal surface to establish a second seal, said second valve means and said valve means bore establishing a normally closed relief passage therebetween from said second seal to said outlet passage;
first biasing means interposed said first and second valve means and applying a first seating bias therebetween adapted to establish said first valve seal until said fluid pressure is obtained, said fluid pressure then overcoming said first seating bias to move said first valve means against said second valve means to close said vent passage; and second biasing means interposed said valve body and said second valve means and applying a second seating bias therebetween to nor-mally establish said second seal until said fluid pressure attains a prede-termined relief pressure, said fluid pressure then overcoming said second seating bias to move said second valve means toward said valve stop surface to open said first seal and relieve said fluid pressure through said inlet passage and said relief passage;

whereby said first and second valve means cooperate to vent-said vapor pressure until said fluid pressure causes said first valve means to close said vent passage and to normally close said relief passage until said fluid pressure reaches said predetermined relief pressure.

9. The vent-relief valve of Claim 8, wherein said first biasing means comprises gravitational means cooperating with a preferred orientation of said valve axis being in proximity to the vertical axis with regard to the earth.