July 11, 1950
c. F. ERIKSON
2,514,570
LIQUID LEVEL GAUGE
Filed Dec. 31, 1949
2 Sheets-Sheet 1
JNVENTOR
CQEL F: E'P/HSON
ATTORNEY
July 11, 1950
c. F. ERIKSON
2,514,570
LIQUID LEVEL GAUGE
Filed Dec. 31, 1949
VI
2 Sheets-Sheet 2
'
i
/ {gr/11:] b
gum!
INVENTOR.
CHEL f‘. E'E/KSO/V
Mam/M
A TTORNEY
Patented July 11, 1950
2,514,570
I
2514.570
LIQUID; LEVEL .GAUGE;z
v
C'arljFfEi'ikson; White Plains;‘_N-:'Y.‘, assignor to> '1
’
Nathan-‘Manufacturing Company; New?Yorky‘
NF'Y-i’ arcorporatiom of 'NeweYorkr
I
'
.
. Applicationllecemhen .31, 194.9,. Serial No‘..13_.6,_2.v_25 .
_7 ‘Claims;aIv (Cl. 737-293") r,
I ‘This invention relates‘ generallytoiiliquid ' level ‘I
light; transmittingfmedium the'level‘ of the liquid’
gauges and moreparticularlyjto those‘wherein‘
for the "reasoni‘thatthe' marks appear "differently
thevl‘ejvel of. the liquid withina‘vesselinaybe ob‘:
served. in an associated sight glassy? '. While‘ the
when‘ within the liquid'than‘ when; above it.
in
invention‘ is‘ . adapted‘ for employment in; deter=
mining the‘ level" of. liquids generally, it‘ is . espe-j
cia‘lly. useful. in conjunction‘ with the. reading {of .
levels‘ of liquid .in tanks,in.relativelyjdark'100a»
tionswhereillumination is necessary at certain
times to make the desired observations...
dium effectively; when desired.
10‘
'
invention are .showntf ‘I
Ili..th'e';;di'aw.i.ngs,l. .1
'
'
'
.
.
but. with itslight receiverin ‘linewithjthe light’
transmit?ngm?dium;
20
known, are externally. .ofi'the liquid andtheirra‘ys'
aredirected. from- without the gauge. chamber to;
I.
'
.
'
'
‘
.
Fi’g. Z'is a front elevational'view of the same;‘
_ Fig.3 is an horizontal sectional view 'alongthe
plane.of‘lineg3-'-3.;in'Figq?;
'
I
' f
" Fig. 4 ‘is. a sectional’view;jsimilar. to Fig.v l, but‘:
Within it and against the. liquidgrespectively;its;
with‘ its light ‘.receiver‘ atright. angles to ' the ‘ light,
In . many .cases‘, . observations . of ‘the
liquidjlevel. .With these. deviceswerc dif?cult,.
owing to.,.undesirable..re?ections...frorn. the; illu:
25
»
30
that'..such.gauges. were of .more orvlesscumbere
some. construction taking considerable space and;
could.,not.be- applied. to locations.- where space
plane of '1i.ne,-B.—,—6. inr‘ie- 5;‘.
,
'
E19. .7 is. a; vertical‘ sectional; vview .of'- a ‘gauge.
suitable to be attached directly to the outenr’wall
0f..a-..tank;,
.
‘
.
I
Fig. 8..f isv apfront‘ el'evati’onal. view of jth'e'fsame,
was. at apremium, asfor instance, to .fuel tanks
of Diesellocomotives .where ya. gauge .must beat-1'» .
tached .closeto ~the .tanl; and whereext'reme.v pro:
partly insection;
.
I
_.
.
f
v
'
.
Fig‘. 9..‘is. an horizontal sectional‘ view. along. the
plane.of._line...9-:-9.in.Fig.,8;
.
v
,
_
‘
F1110 ‘is a fragmentary..verticalseotional view
'
of..a ;modi?ed..form . of .light. receiver... suitable for
applicationatoja. gauge as. shown, .for instance; in
' It is_.-the.principalrobject of the invention to]
overcome the. before. recited. shortcomings- of.
to atank, a lighttransmittingmedium disposed
.
Figcjis an.,horizo;ntalsectional view along the
sources. of. light. were. not strong_..enough_ to; ef'-. -
present gauges, by providing in a-lgauge attached
,
shbwn..in.Fifg‘.-.4‘; '
chamber .or,-_,-the ,glass, tube; further; existing.
fectively. light. up.the,.gauge. It. was .also .found;
transmittinamedium; J
Fig.‘ 5' is?a vfi‘onti elevationaljlview .‘of. the gauge
minatingI.member..,against. thev glassbf ' the gauge.
'
.
Figri I'jiS‘ .a .vertical: sectional ’ view“ of_ ' "a I gauge.
erally within .a. glass tube or... a,_chamber;with“;a .
jections . from the gauge...must. be. avoided...
‘
'
embodying __the;principles" of the ‘ invention, with
the illuminating means separate vfrom the gauge,
transparentf front‘, the. tubej'jor 'ch‘amb‘ergbeingl;
to..vbe_,noted.j The illuminating ag$IllIS,'____SQ ffafr
‘
Still‘'ifurther'jobjects ‘will become-apparent in,
the following ‘ speci?cation" and'jthe'. accompanying _'
drawings in‘..whichj preferred‘embodiments of ' the
or..,the...bot_tom, ,to. illuminate‘. the, liquid _f or ,better
observation -of ‘its meniscus. The‘ liquid is.) gem
connectedto ,the tank the contents .ofgwhich‘aré"
various‘types theprincipal objects Of‘ the invena'
ti'onfnamely; a" light‘transmitting medium in di'-_
rect“'cont'actj ‘withv the .liquidgtd be. observed; and
simple‘. ande?hiient~ means to illuminate'_ the me-'
In the usual form, of.liquidleveligauge in ‘dark
locations. or. at night, the .level'oi ‘the liquid {can '
be; observed by, lamps which are ‘placed. either in ‘
front .or. in back .of .the ga'ugejor. even at‘ the [top
meniscus...
I
Still‘ ‘another vobject. is'to provide in‘ gauges (of
40
Fig.7.;
,
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'
_
'
‘
'
Fig.1]. is a.fragmentary-wertical sectionaLview
of. anillhminatihgmeans. suitable for direct ‘ate;
tachment'. .to . gauges. of. any... of. the, - types ‘ illus:
wherein the-.levelof the-liquidin thetank can
be.‘ observed, through a transparent. plate. or the
like and in-whichthe light. transmitting medium 45 Fig. 12 is a modifiedhorizontal..cross;sectional
view. of.Eig.1 9.-,embody_ing..shi1t;off..va1ves; ‘. _
is, pre-ferably,.surrounded. by the liquid‘ inwthe
Fig;- 13 ; is a .fr agmentary , front} elevational .view
chamber the level of. which corresponds to that
within the chamber ‘connectedwith . the tank. and.
trated;..
of the‘liquid'in the tank.
}
.
"
.
‘
‘
.
I
‘.
’
Another object is to'villuminate the lighttrans
thereof;..'
vFig.l.1¢i.;is' a.fragmentarywvertical‘
Y
sectionalwiew
.
'
mitting mediumby simple means which may -be 50 alongthe plane. of lineillié-lid. in Fig. 12;‘ ,7
removable or attached" to . the 2 gauge ‘structure,- so
that the- gaugesimay- be used; if» so desired; with
out; the: illuminating means.
A- further object is to providethe- aforesaid
15 ~- isan= enlarged fragmentary. ‘vertical
view,» partlynn ..section,,.of ..the.,1ight transmitting
medium. surrounded partly by‘ v a liquid" .in.‘ . the.
gauge;=with the transparent fronhcover. removed
medium ;with:marks~ which; indicateclearly. onathe 56 for; sake, of.~,_-clearness;- indicating .on. themediumv
2,514,570
the different appearance of the marking above
and below the liquid when viewed through the
front cover; and
Fig. 16 is an enlarged fragmentary vertical sec
tional view of the light transmitting medium
showing the marking along the plane of line
|6—-|6 in Fig. 15.
'_
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Like characters of reference denote similar
parts throughout the several views and the fol
lowing speci?cation.
shape of the marks above and below the liquid
level is now clearly noticeable and the level of
the liquid in the chamber more readily observ
able. It is to be noted that the rod is the only
light source and is disposed within the chamber
of the gauge whereby undesirable re?ections on
the plate 24 from outside the gauge are entirely
avoided.
While the marks on the back of rod 30 are ‘
shown in the shape of conical indentations 3|,
Referring more particularly now to Figs_._>1‘,"2 ‘ e
and 3, 20 is a gauge body having an open‘cham
ber 2|, connections 22 and 23 at the top'and'bot
tom, respectively, to be attached to pipes in com
munication with a tank the contents of» which‘
are to be observed in the gauge._ 24 isa trans
parent plate and 25 a gasket at its marginal
portions held ?uid tightly against a face 25
surrounding the opening'of the chamber 2| by
it is obvious that any other shape or manner of
marking may be used instead. The curved sur
face of the rod 30 serves as a lens above the liquid
and thus makes the marks appear differently
. above and below the liquid.
Itis also possible, of course, to omit the marks
* altogether and depend for illuminating the gauge
upon'the rod 30 only receiving light from the
light receiver 29. This is particularly advan—
tageous with dark colored liquids in the gauge
means of frontal strips 21 and bolts and nuts 28.
and tank. The dark colored liquid permits only“
The bottom of the gauge body 20 is extended in.
very little light from the rod 30 to pass through
a funnel like shape at. 29 to form a light receiver.
30 is a light transmitting medium made in this
it giving it an opaque appearance, while the r'odf
above the liquid in the gauge is brightly illumi
embodiment of the invention of a‘transparent
rod of, preferably, round, cross section. This 25 nated, thus indicating clearly the level of the,
liquid by this contrast of light. The term “rod"
rod may be of “Lucite,” or other suitable mater
is to be interpreted broadly as a longitudinal
rial. At the side of the rod facing the, rear wall
of the gauge, are a, number of round conically‘
member of any suitable cross section.
V
In Figs. 4, 5 and 6, a slightly modi?ed form of
shaped indentations 3|. The rod is inserted
lengthwisely into the gauge, its lower end being 30 gauge is shown. Gauge body 2|], chamber 2|,
located within the‘ light receiver 29 and its upper ‘
connections 22 and 23, transparent plate 24,;
end in the top of the gauge. body 2|]. Packing
rings 32 at the top and bottom hold therodlfluid
tightly in the gauge. 33 shows‘ in dotted lines
gasket 25 are substantially similar to the gauge
' shown in Figs. 1, 2 and 3 and the same reference.
the upper end of a manually carried ?ashlight
within the light receiver 29 which serves as an
numeralsare used. ‘A front plate 34 having an
elongated aperture 35 is held against the trans-f
parent plate 24, by suitable bolts and nuts .36.
The bottom of plate 34 is extended at 31 and
shaped to form a light receiver 38. A light trans
mitting rod 39, similar to rod 30 of the gauge
tion is as follows:
.
. .
'
40 shown in Fig. 1, has its lower part outside of the
gauge body bent at a suitable angle at 40, so
The gauge is applied to_ the tanklby means of
that its end terminates within a central opening
pipes screwed into connections'22 and 23. ,Pipes,
4| of the light receiver 38.
of course, could be omitted, and the gauge ‘body
so arranged that its connections 22 and 23, in
In these figures, the marks on the rod 39 have
stead of being right-angled, are fastened directly . been omitted for sake of clearness and because
their use is optional, as explained before. The
to the tank in any convenient manner as ex
plained more in detail later on. The length, of
liquid of the level can be observed in this gauge
the gauge may be either .equal to the length of
the same as in the gauge shown in Figs. 1,2 and
3. The ?ashlights, however, can be applied .to
the tank, or of a length which makes‘it possible
to observe the critical level of the liquid within ' the light receiver at right angles to the previously
shown application which may make this gauge
the tank.
, 7
better adapted to locations where space below the
Under daylight conditions, the level ofthe ?uid
will be observed through the transparent ‘plate
gauge is limited. The side of the bent part 40
24. The indentation 3| in the rod ‘30 appear‘ per
of the rod, projecting exteriorly of the gauge
fectly round below the level of the liquid, while 55 body is, preferably, painted a dark color or other
wise treated to prevent loss of light therethrough.‘
above it they are of an elongated shape asin
dicated by 3|a in Figures2 and 15 andmade to
. V In Figs. 7, 8 and 9, a gauge is shown which can'
appear so by that part of the round ,rod above
be applied ?atly against the side of a tank.‘ -In
the liquid the curved surface of which serves as
thisgauge, a body 42 has a ?at back 43 and an
a lens. By this di?erence, the level of the liquid
open chamber 44. The top and bottom of the
chamber 44 is connected'to the tank by, respec
can easily be noted. This difference is still fur-}
ther accentuated by painting the back of the
tively, right angled channels 45 and 46. 41 isia
transparent plate covering the open face of
gauge chamber 2| which" faces the marking 3|“
chamber 44 and held against a gasket 48 sur-v
on the rod 30 a dark color ‘or any shade contrast
ing to the liquid to be observed. v
I
65 rounding the open face by frontal strips 49 and
bolts and nuts 50. Bolts and nuts 5| secure the
In dark locations, or at night, holdinga ?ash
body 42 against the outer wall of the tank.v 52 is
light within the light receiver 29, as indicated in ‘
a gasket interposed between the wall and the flat
dotted lines in Fig. 1, will illuminate the gauge,
back 43 of the body 42, perforated to conform to
i. e. the rod 30 will become luminous and light up
illuminating means.
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I
‘
The gauge so far described embodies the ine
vention in a very simple form- Itsjuse and func
the chamber 2| and the liquid therein; ' Project
the terminals of channels 45 and 46 to make a
ing the rays of light upwardly through the‘rod
to be brightly illuminated providing secondary
fluid-tight joint between tank and gauge.
At the bottom of the gauge body 42 is a funnel
shaped light receiver 53 fastened to the gauge
light sources withinithe ,chamber'2l. ' This'is
body by means of screws 54.
30 causes the lower halves of the ‘indentions 3|
55 is a light trans
shown in Fig. 15. ‘The difference'between the 75 mitting rod having its lower end terminate within
asters-101?.
tne.-zreceives<saé and held‘i?uid'itightly wlithinlthea;
"me-roar
‘
that is the light receiver or the lamp housingi‘
5r-i5ex===
tends lengthwiselylit rough the chamber;<f4'¢i‘and-1'P
may-be‘. placed-Tat bothiends offthefgauge ‘whereby
rests é'witl'i'¥its1.-upper'> endliwithini a irecessiffic'le 'at‘tlie .1
a“ symmetrical;- andi advantageous:- structure-1is:v '
top of" triechamb
The 5‘use ‘and ilirctio'ri-i ofi'fthei; gauge shown; in
achieved;: In! place :‘ofia soli‘drsro'd; r; a : hollowr rodi
or‘ tube may- be used; The’: ‘cross section. need» lnotl';
be alroundg-ibut couldlibeofi'ianyi suitable: shape by‘ I
Figs. 7 8‘i-and1'95
described‘.
T,
In{theconstruction-illustrated;5
d the "same : ash-those‘: prevli‘ously'
hQWl- .
means'aofwhichithez le‘ns'i-eii‘ect; i describediihereiin; .
carpi-be! achieved iiwhe're ‘markings: are <iuse'd; i and:
evergi‘tlieii-rod'ii55i can’rlbe assembled with the re
ceiver 53 as a unit, if so desired, and thus inserted
couldib'el-l'ofiany r‘crossisectioniadapted ifo‘r the-pure
In Figs... 12,..13..and.~ 1.41,, a. slight modi?cation . of
pose‘where' no .=m'ainkings5areaused?andino parti'cuef:
lari' lensve?ec't ji'slneededa-li. Theifftel‘miif‘i?dii ‘there-‘w
the‘body' of the ‘gauge 'shows'inimg‘s. 7,0. and 9.
is disclosed. In these ?gures parts'whi'cl'i are the
fore -:is toibe interpreted broadly; as statedrbeforev
It is also conceivable thatiar?uorescentior
into the gauge:
.
‘
same carry the-samereference- numerals.
‘lanl'lampv oi elongated‘:cylindrical?‘form.:may .be
used“ ristea‘di'ofl the; light; transmitting; rod fillusrr
trate'ds In; such." anc-‘applicatiom if= markings1;..are=
desired; .theyimustssb'e "placedlonthati side£ofz the}
At the
bend .oi'each of the channels llirand 66 is inserted
as-valvet plug-m8 which isfada-ptedzwto hex-rotated
within an: enlarged portions :59?!'__'0f;' each pop :the
channels,‘v the upper channel-'45rbeing shownin
lamplneariest theltransparent.viewingsplate. but,"
these ?gures:v PlugqSB is bored-nut interiorlygqat
20 becauserthere isfrnoiil'ensiefiect: as withxthe light"v
BOVand‘hassa transverse bOI‘EnQlrSO as to'vafford
communication between the chamber Meandgthe
transmitting rod; 'tlr'etizmarkingsta will; 11011131013631?“
differ‘entlyrabbveior :b'elowrthevleuelro f" heiliquidii
tankr byway/10f channel 45. , An=-.exteriorly:"pro
l-lowevenla .Whél'éfa 3. dark sscdloredz' liquidl‘iiscto be:
jectingaportion 62 of theplugqiskslotted air-63am a
obs'erved; the slights'from-‘the lamp wouldzpenetra'ta
direction parallel to tha-taof-w-bore 6|.
this a 25 the iliquidiion lyizfaintlyj‘ so‘. that‘ the‘ :part rofrithe:
paokingjring-iaround the plug eats, prevent leaks
lamp: aboueat-he liquid :"woul'di be wery- bright» by“:
from the gaugechamber. 65 is a spring washer
bent so as to be‘ h'eld’ivithbne part against the
contrast when switched on}:facilitatinguobser as;v
tionsiwithout‘sthe \llSGE'OfY markingsl': Aiconvenient
switeht'fomthet > lammcambenplaced: immediately:
belo‘wa-the gaugezbioidyi
gauge'ibody 42 by one ofzithe'i'bolts and nuts 5! ‘
andi with "another .part: to"; engageiaaireces'svoni the
plug to prevent the plug becoming disengaged
It is apparent that I have provided a simple
gauge suitable for attachment to a tank for the
from the gauge body.
In actual use, the slot 63 of the plug i513 con
forms to the position of the bore Bl with respect
to the channel 45. If in an horizontal position,
as shown, it is indicative of communication be
tween the gauge and the tank; if turned at right
angles, it indicates that the channel is closed and
that repairs to the gauge can be made without
observation of the level of the liquid therein
which is extremely compact, occupies very little
space, can be easily illuminated when desired, and
is equipped with means which make possible an
easy reading of the liquid level during daylight
as well as when dark.
the liquid in the tank running through the gauge. _
In all other respects the function of the gauge is
identical with those previously described.
In Fig. 10 a modi?cation of the light receiver
53 of the gauge shown in Fig. 7 is disclosed. The
receiver in Fig. 10 consists of a plate 66 held to
the bottom of the gauge by screws. The plate
has a depending right-angled portion 61 in front
of the gauge body, cupped out to form a light
receiver 68. The light transmitting rod is bent
Many changes in the form, proportion, com
bination of parts, and minor details of construc
tion may be resorted to without departing from
the principles or sacri?cing any of the advantages
of the invention as de?ned in the appended
claims.
What I claim as new, is:
1. In a liquid level gauge having a. chamber
connected to a tank containing a liquid, a trans
parent member in the wall of the chamber, a rod
of transparent material within the chamber hav
at right angles at its bottom to terminate within
a central aperture of the light receiver similar to
ing light conducting qualities and extending
the gauge shown in Fig. 4. With this arrange
ment the light receiver complete with the rod can
source admitting light into the rod from the ex
terior of the chamber for observing the level of
also be assembled as a unit and so inserted into
the gauge.
'
through the liquid in the chamber, and a light
the liquid within the chamber through the trans
55 parent member.
In Fig. 11, instead of a light receiver as previ
ously described, a lamp housing 69 is attached
to the bottom of the gauge by screws 10. An
electric bulb ‘H is suitably socketed Within the
2. In a liquid level gauge according to claim 1,
the chamber having a background contrasting in
color to that of the liquid in the gauge.
3. In a liquid level gauge according to claim 1,
housing. The light transmitting rod terminates 60 secondary light sources on the side of the rod
in the top of the housing. The functioning of
deriving their light from the light source exterior
this gauge is the same as those previously de
of the chamber whereby the level of the liquid
scribed. The light, however, is permanently at
can be ascertained by the different appearance
tached and can be switched on or off, as desired.
With this arrangement, too, the lamp- housing 65 and brilliance of the secondary light sources
above and below the level of the liquid when
complete with rod and bulb can be inserted into
viewed through the transparent member.
4. In a liquid level gauge, a body having a
While I have shown in the drawings several
chamber, connections to a tank in communication
different types of gauges all embodying the prin
ciples of the invention, it is obvious that many 70 with the chamber, a transparent member in the
wall of the chamber, and a light transmitting
other modi?cations may be made. So, for in
rod in the chamber, one end of the rod terminat
stance, instead of providing for the light source
ing exteriorly of the chamber, the body having
at the bottom of the gauge, it may be provided
a funnel-shaped extension surrounding the ex
for at the top, or at any other convenient point.
In those gauges where a straight light transmit 75 teriorly terminating end of the rod for the
the gauge assembled as a unit.
21, 514,670,,
8.
7,
optional reception of an illuminating means for
in the wall of the chamber, a light transmitting -
the rod.
rod in the chamber, one end of the rod terminat
ing exteriorly of the chamber, and a funnel
.
5; In a liquid level gauge, a body having a
chamber, connections to‘ a tank in communica
tion- with the chamber, a, transparent member in
‘ the wall of the chamber, a funnel-shaped exten
, shaped extension surrounding and supporting the
exteriorly terminating end of the rod for the re
ception of an illuminating means for the rod,
j sion at one end of the body, a light transmitting
rod in the chamber, one end of the rod projecting
the extension and rod supported thereby form
ing a unit adapted to'be fastened to the body.
‘ exteriorly of thechamber and being bent to ter
CARL F. ERIKSON. ; M
minate within the funnel-shaped extension of
the body, the extension being adapted to receive
an illuminating means for the rod, the sides of
, the exteriorly projecting end of the rod being
coated impervious to light.
REFERENCES CITED
The following references are of record in the
?le of this patent:
'
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UNITED STATES PATENTS
.6. In a liquid level gauge having a chamber 15
connected to a tank containing a liquid, a trans
Number
Name
Date
parent member in the wall of the chamber, a. light
545,727
, transmitting medium in the chamber, and means
' 646,022
754,034
767,486
1,288,377
Fletcher et al _____ __ Mar. 27,
Zoanetto __________ __ Mar. 8,
Metten __________ __ Aug. 16,
Bryan ____________ __ Dec. 17,
1,926,945
2,246,464
2,289,374
Hipp ____________ __ Sept. 12, 1933
Gerber __________ __ June 17, 1941
Martin ___________ __ July 14, 1942'
fo'nilluminating the medium from the exterior
‘ of the chamber, the medium having a curved face 20
‘ nearest the transparent member and markings at
its opposite face, whereby the medium distorts
‘ the markings above the level of the liquid by
virtue of a lens effect of the curved face of the
medium making the markings appear differently
above and below the liquid when viewed through
the transparent member.
'7. In a liquid level gauge, a body having a
chamber, connections to a tank in communica
tion with the chamber, a transparent member
Rockstroh ________ __ Sept. 3, 1895
1900
1904
1904
1918
2,303,154
Armstrong ________ Nov. 24, 1942
2,484,329
Angel et a1. ______ __ Oct. 11, 1949
FOREIGN PATENTS
Number
197,538
Country
Date
Great Britain ____ __ May 17, 1923