Note: Descriptions are shown in the official language in which they were submitted.
Backgro'und of the Invention ~
.:-
This invention relates to fuel pumps and, more particu-
larly, to a crashworthy fueI pump capable of withstanding --
extreme forces such as occur during a crash without leaking --
fuel.
Because of their location in the engine compartment of
an automobile, fuel pumps are susceptible to damage during
a crash as the result of being struck by debris flying '~
about in the compartment. As a consequence, fuel leaks from -'~
the pump may occur. The presence of gasoline in the engine
compartment due to a broken fuel pump creates a great risk .'~
of fire and potential harm to bo~h the vehicle and its -~
occupants.
Fe.deral Motor.Vehicle Safety S~andard (FMVSS).30 was
15 issued in an attempt to reduce the hazards attendant the '~
location of th.e fueI pump in the.engine compartment by ''~
requiring that the risk of damage.to a fuel pump. during a .-.... -'.. ''
crash be minimized. To comply with this standard,.various -'.'...... --'-.
schemes have been proposed to shieId the fuel pump or other~
wise protect it from flying debris. However, these protective
shields add weight .to the.vehicle, may be difficult to fit
into already crowded engine compartments, and may not always '.''.'-'-'''.
prevent an object from.striking a fuel pump.
Summary o'f:the'Invent'ion ''~
Among the several objects. of the present invention ''-'''-'
may be noted the impro.vement to a fuel pump by which the'fuel '~
pump is made crashworthy; the provision of such an improve-
ment by which~the fuel pump will not leak fuel when struck .''.'.'''.
by an object.even though the'fuel pump is. deformed; the ''........ ''.
.30 provision of.such a fueI pump which has .substantially the .~
same'envelope as a conventional non-crashworthy.fuel pump .'.... '.''.. -
so as to be readily installed in the. engine.compartment of -'''.'-
a vehicle and take.up substantially the'same. volume therein. .-.-'-.''.
Br.iefly, the improvement of the present invention comprises .
35 a lip formed at the open end of a fueI pump body, the lip .'~
being bendable over the outer margin of a diaphragm after :"'.'.::'
the diaphragm has been inserted into the body thereby to ~.''.''
form a fluid seal between the body and the diaphragm, the
....
b, ~
,: .'~
,', ' ~
- 2 - -,,,,,,:
seal being capable of withstanding abnormal forces such as
occur during a crash whereby the seal retains its integrity -
and no fluid leak.occurs. Other objects and features will ,-
be in part apparent and in part pointed out hereinafter. ',~
,5 Brief Des'cript'ion''o'f't'he'Drawin'gs
Figure'l is a sectional view of a conventional fuel
pump installable in the engine compartment of a vehicle; and',:-,"~
Figures 2 and 3 are sectional views of a portion of the
fuel pump illustrating the improve~lent of the present inven- '.-.'
10 tion. '--''~-
Corresponding reference characters indicate corresponding '-''."'',
parts throughout.the'severai,v.iews of the drawings. -,'.',
'~Des'c'rip't'ion 'o'f a Pre'fe'rr'e'd Emb'odi'ment --'-'-''--''
Referring to the drawings, a, fuel'pump F, for.use in an ,
.15 automotive, fueI sys.tem comprises a pump.body, generally '.,~
indicated B, which is of one-pie.ce, thin-walled, sheet'metal'.'."'"'.''
.
. construction. Body B has a first po.rtion P'l in which are ---
formed two integral deep-drawn cylindrical cup-shaped projec- '.-.'.'.
tions, one of which is partially shown in Figure 1 and is
20 indicated by.reference numeral 1. One of the projections .,:''','
defines an intake cavity for the .fuel pump and the,other
projection defines a discharge.'cavity.for the pump. A '-',,','-,,-,'
properly or.iénted check.va,lve'(not shown) is l:ocated in each ,',-','.-',-',','
: cavity, to.control,:fuel,.flow into and out of the fuel pump,:,,',,-"::
25' and appropriate,fittings (al.so not shown~ are iocated at the',.'-',',','
outer end of each projection, for connecting the fuel pump'''-'',.':
into the,.fueI sys.tem. Check valves and fittings of the type''.'''.-'
: shown in United States Paten~.3,'096,722.to Fitz.gerald et al,
issued July 9, 1963, are'il:lustrat.ive'of tho.se which'may be' -.-.. '.'..30 . used in,.fuel pump:F.
Body B has a ,second portion P2 of a shallow cup shape .. '-'-,
h~ving an end wall.3 and a.flaring annular peripheral wall,5 ':':'.''''.
forming a .fuel pumping ch'amber 7, One end of each cavity 1 -.. '`-
is in, fluid communication ~ith the pumping chamber. The .'`-'.'`
35 lower end of body portion P2 is open. ...
An annular diaphragm 11 closes pumping chamber 7. The .:''
diaphragm consists of a relatively thin disk of flexible, :::
fuel resistant material such'as a suitable synthetic rubber.
, . ...
.
:
'
' ' : .,
.
oa~
",,,:
In its unstressed condition the diaphragm is essentially
flat. The diaphragm is insertable into the open end of the ,---
second portion of body-B. :-
Means, indicated generally 13, flex diaphragm 11 to pump --'
5 fuel into and out of pumping chamber 7 through the respective -''~-'
intake and discharge cavities. Means 13 comprises a diaphragm '~
actuating rod 15 and a spring 17. Diaphragm 11 is sandwiched '','',''
between a pair of backing plates 19 and 21 respectively. Rod ',',',','-,,
lS extends through the backing plates and the diaphragm and ,',~"'
10 the end of the rod is spun over. One. end ,of spring 17 seats '.,~
against the underside'of,plate 21. A rocker arm 23 is
operable by an engine driven :ec.centric cam (not shown). The ',-'-',,-,",
inner end of the rocker arm is attached to the other, end of ''-,---,'.",',
rod '15 an~ pulls the rod downward as it is rocked by the -,'-.'','.
. .
15 cam. .This pulls diaphragm 11. downwardly and creat~s the ,~
,intake stroke of the pump. Spring 17 pushes the diaphragm ,,.,-,
,upwardly at the end of the intake stroke to produce the dis- ,',-,
charge:stroke ,of the pump. .-'.'.-,
Means 13 is housed in a housing 25. The housing has a '''''''
20 hollow,conical pump head 26. The pump head has an outwardly '~
extending circumferential rim 27.the upper face of which is
downwardly and outwardly,sloped. Body B and housing 25 are -~
assemb.led as is well known in the ar't with the outer'margin
of diaphragm.lL clamped between the abutting surfaces, of the -'-.,,.''
25 body and the housing. ~ .. '.. ''
,An improvement of the present invention comprises a lip -'.'
29 formed around the open end of body.portion-P2. As shown . ,-.,','.-.
in Figure'2, lip 29, which ex~ends aro~md the periphery of -','.'-
the open end of body,portion P2, is bendable over the ,outer '.. '-
,30 margin o diaphra'gm 11 after the,'diaphragm is inser.ted into .'.''.'''
the open end ,of the body. , This-creates a, f.luid seal between -,'.-
the'body and th diaphragm. . A cir.cular ring.31 is now fitted ... ''.,-
around the body and the housing to clamp the two together. ',
Ring.31 has an inturned lower margin forming a lip 35. The ''..''-
35 inner face of this lip abuts the.bottom outer surface of rim '.''
27 when the pump is assembled. The ring has an upwardly
extending circumferential side 37 whose height is such that --
the side.'extends beyond the joining surfaces of body B and '',-~
~44~)3
- 4 ~
housing 35. The upper portion of side 37 is crimped over the
top of body B after the body and housing are brought into -:-
~ating abutment so as to clamp the body and housing together ."--
as shown in Figure 2. ,,~
As a consequence of the above described improvement, a .'~
fuel pump F is made cras'nwor.thy in that a,fluid seal is ,,~
created which can withstand severe distortions of the pump. ,~
It has been experimentally, found that the seal created
between the body and diaphragm remains intact even when the ""~
10 body is essentially,flattened such as might occur if the .
pump were struck by,flying, debris. Thus, the danger of fuel
, leakage, following a crash is substantially reduced as is thé '",,-,-
: ' necessity of brackets or shields,for the fuel pum,p. At the-
: same time, the fuel pump envelope is. es,sentially unchanged '",.",',,
15 and a crashworthy, fuel pump of the présent invention will -'"-'.,',.,',-,.: occupy substantially .the'same space'in àn engine compartment ','.',','.'
: ' ' as a conventional non-crashworthy,fueI pump. '~
Re.ferring to Figure.3, backing plate 21 has a circum- -:--'
'- : ferentiai skirt.39. .The length of lip 29 and the height of .....20 skirt 39 are made sufficiently great.so the outer end of the ,',-.'
skirt cannot contact diaphragm 11 if the body of the. fueI '''.'-''
pump is so. deformed that thé'skirt and body/diaphragm as.sembly .~
come into contact; , This prevents the diaphragm from being .'-.'.-,'-.'.'-
punctured by the skirt and thus,further safeguards against :.:,,,,,'
25 fue~ le,aks. .Additionally shown in Figure.3 is a.clamping --.. ",~
ring, ~ ' which may be. used to.joi~jbody.B and housing 26 to -',.,-'.. -,.
form a,.fuel pump as,sembly. Ring,~ has i~s up.per. end bent '~
back upon it.self prior~to or. during the:-crimping operation.
In view of .the'above, it will be seen that the :several ... -.-
.30 objects of the invention are ac~ieved and other a.dvantageous
results obtained. .. '... ~
As. various changes,:could be made in the above construc- ,.. ,.. '.,.-.'.
tions without departing, from the sco.pe of the invention, it .'.
is intended that all matter contained in the above descrip~
tion and shown in the accompanying drawings shall be inter~
preted as illustrative and not in a limiting sense. .-
;,. ....
.
