вход по аккаунту


Патент USA US2134686

код для вставки
Nov. 1, 1938.
5 Sheets-Sheet 1
Fi'led Jan. 15, 1956
“lJ-nudV‘ JNl"il?/Vr
Nov. 1, 1938.
2,134,686 ‘
Filed Jan. 15, 1936
5 Sheets-Sheet 2
44 68
Nov. 1, 1938.
Filed Jan. 15, 1936
5 Sheets-Sheet 3
W ‘V‘ 7144/,
NOV- 1,- 1938’
Filed Jan. 15, 1936
5 Sheets-Sheet 4
Mm” 1K0: ZA/mrr
- ‘Nov.
l, 1938.
Filed Jan. 15, 1936
5 Sheets-Sheet 5
94 9f 64
Patented Nov. 1, 1938
Warren H. De Lancey, West Spring?eld, Mara, as
aignor to Gilbert 8a Barker Manufacturing Com
pany, West Spring?eld, Maaa, a corporation of
Application January 15, 1936, Serial No. 59,254
1 Claims. (01. 108-113)
‘This invention relates to improvements in ap
paratus for pumping relatively volatile liquids,
such for example as gasoline. The pumping ap
paratus has been particularly designed to meet
the special conditions which are encountered in
dispensing accurately measured units of gasoline
and, while capable of other adaptations, is espe
cially suitable for the particular use described.
The invention seeks to utilize in dispensing
apparatus of this class, the well-recognized ad
vantages which the centrifugal type pump has
over the displacement type pump which at pres
ent is the type most widely used in such dispens
ing apparatus. ' The centrifugal pump is smooth
[5 er and more quiet in operation; will deliver the
required quantity of liquid in a minimum of
time; consumes less power; enables substantial
savings in manufacturing costs; and is less likely
to require servicing. In addition, this type of
pump can readily be utilized to secure through
the centrifugal action of the pump itself, a very
gasoline or the like and for effecting the separa
tion of air from the liquid and the scavenging
of the separated air.
The invention has many other objects, relat
ing to improvements in the structure and in
the arrangement of parts in a motor-driven
pumping unit of the class described, and these
will best appear as the detailed description pro
The invention will be disclosed with reference 10
to the accompanying drawings, in which:
Fig. 1 is a. small scale elevational view of a
gasoline dispensing apparatus embodying the in
vention, certain parts of the casing of the appa
ratus being broken away to reveal interior mech 15
Fig. 2 is a fragmentary elevational view taken
at right angles to Fig. 1;
Fig. 3 is a sectional elevational view showing
in full detail the liquid recovery device used in 20
connection with the air separating means of ‘the
e?icient separation of air from the pumped liquid
and a small displacement pump, necessary for
priming the centrifugal pump, can be made to
driven pumping unit, drawn to a larger scale,
the lower and pump portion of the unit being 25
shown in section;
Figs. 5, 6,7, 8 and 9 are sectional plan views
taken respectively on the lines 5-5, 6-4, 1--'|,
8-8 and 9—-9 of Fig. 4;
perform the additional function ‘of scavenging
the separated air.
This invention has for one object to provide in
a pumping apparatus for gasoline or the like,
having a centrifugal pump designed to pump
30 the liquid and also cause, through its centrifugal
action, a separation of air from the liquid and a
displacement pump for priming the centrifugal
pump and scavenging the separated air, an ef
fective means to insure that the air-free liquid
35 discharged from the centrifugal pump maintains
its air-free appearance when delivered to the
With the forms of centrifugal pumps hereto
fore proposed for use in gasoline dispensers, it
40 can and does happen at certain times and under
certain ‘conditions, that the gasoline will become
partially vaporized in the discharge chamber or
passages ‘of the centrifugal pump and, when this
occurs, the liquid discharged has a foamy- ap
45 pearance due to the presence of innumerable
small bubbles of gasoline vapor.
The air-free
liquid does not actually ‘appear so and the cus
tomer naturally objects.
It is not enough to
free the gasoline from air but it must also be
50 delivered to the customer in clear condition with
an air-free appearance and this is e?ected by
my invention.
Fig. 4 is an elevational view of the motor
Fig. 10 is a fragmentary cross sectional view 30
taken on the line Ill-40 of Fig. 9;
Fig. 11 is a sectional plan view showing a modi
fication in the shape of the inlet port of the dis
placement pump;
Fig. 12 is a fragmentary sectional view, taken 35
similarly to Fig. 4 and showing a detail of the
centrifugal pump;
Fig. 13 is a fragmentary sectional elevational
view, taken similarly to Fig. 4, and showing a
modi?cation in the centrifugal pump construc 40
tion; and
Fig. 14 is a sectional plan view taken on the
line l4-l4 of Fig. 13.
Referring to these drawings; the invention is
shown in Fig. 1 embodied in a gasoline ‘dispens 45
ing apparatus of the so-called meter type. The
apparatus, therein illustrated in more or less
conventional form, is intended to show the usual
environment in which the invention is used, and
will serve as an illustrative example of one of 60
many types of such apparatus with which the
invention may be used.
As shown in Fig. 1, the apparatus is for the
most part contained within a casing l5, having
upstanding column-like corner portions it from
55 ‘improved structural combination for pumping'
The invention also has for an object to pro
vide, in an apparatus of the class described, an
which most of the parts are supported. This
casing is closed at the top by a cap l1 which
usually carries an ornamental globe it. The
through the outlet. The gasoline accumulating
in chamber 44, eventually raises a ?oat 52 which
is mounted to slide on a guide rod 63 ?xed to the
lower wall of chamber 44. The rising ?oat 52‘
mounted near the lower part of the casing, rest
ing on a plate is which is secured to the‘ portions operates through a lever 64, pivoted at 55 to
II. The unit is fixed to said plate by bolts 20. raise a valve 66 and allow gasoline to enter a
pipe 61 which, as shown in Fig. 1, extends down
This unit includes an electric motor II,‘ on the ‘wardly
and is connected to suction pipe 29.
upper end plate 22 of which is formed a box 23.
10 This box houses the usual control switch which Valve 66 opens from time to time as necessary
pumping unit, shown separately in Fig. 4, is
has an operating lever 24. The switch may be
operated by a lever 26, located outside casing II
and ?xed to a shaft 26 which extends inside the
casing and carries an arm 21, connected by a link
15 20 to lever 24. The part2!’ is a ?tting for con
nection to a conduit through which the electric
wires are led to the motor. This part 22' is con
nected to the casing 22 by a screw 2}’ on which
the part 22' may swivel.
The motor-driven pumping unit draws gasoline
up from an underground supply tank (not
shown) through a suction pipe shown in part at
29, and in the suction pipe is theusual check
valve which prevents downward or return ?ow.
to prevent undue accumulation of gasoline in
chamber 44 and closes before all, the gasoline in
the chamber is exhausted so that air cannot pass
back through pipe 51 to the suction pipe 29.
The apparatus, thus far described, will serve as
one illustrative example of the general class with 16
which the invention may be used. The invention
is more particularly concerned with the pumping
unit, wherefore it follows that the details of the
apparatus described are not essential and that
the invention is not limited thereto.
The pumping unit is best shown in Fig. 4. This
unit, as already described, is driven by an elec
tric motor 2i, having the end plate 22 and an
Gasoline is discharged from the pumping unit other and specially-formed end plate 58,-—such
through a pipe 30 which is connected to the ‘ plates being suitably held together as by a series 25
inlet of a meter ii. The meter may be of any of tie rods 69. These rods are threaded into lugs
suitable type and has associated therewith‘ any on the upper end plate and slldably fit and pass
through corresponding lugs 60 on the lower end
suitable form of registering means, herein con
ventionally indicated at II,‘ which are driven plate. Nuts 6i, threaded on the lower ends of
from the meter by a shaft 33. The gasoline rods it, serve to clamp the head 58 in place and 30
also enable its convenient removal from the rest
leaves the meter by way of a pipe 34 which'ex
tends through the casing I 6 for connection to a of the motor whenever necessary or desired.
This end plate 58 is hollow cylindrical in form,
?exible hose I6, having at its delivery end a hose
nozzle ‘36, equipped with a normally closed valve closed at its lower end by a wall 62, from which
which can be manually opened by a lever 31. upstands in concentrical relation a hub-like por
This nozzle is of the same general type as is tion 63 of stepped cylindrical formation. This
shown in U. 8. Patent No. 1,870,918, granted portion 63 is connected to the cylindrical wall by
August 9, 1932, on an invention of Joseph A. a series of radial ribs 64 (Fig. 9) arranged in
Logan and may, and preferably does, have the angularly spaced relation. The plate 58 at its
outwardly opening check valve shown in said lower end has an annular ?ange 65, resting upon 40
patent. Usually and as shown herein, there is a corresponding ?ange 66 formed on a lower
" interposed between pipe 34 and hose 36, a visible casing member 61. It also has a cylindrical
discharge indicator 38 of any suitable form. ?ange 66 ?tted into a corresponding recess in
When the apparatus is not in use, the nozzle 36 the lower casing 61. A gasket 69 is interposed
is hung up on a support 39 (see also Fig. 2) ?xed between ?anges 65 and 66 and a gasket 10 is 45
to and projecting outwardly from casing I5 and interposed between the end face of ?ange 68 and
when thus hung up, movement of the switch the lower wall of the recess into which it fits.
lever 26 in the direction necessary to start motor The two ?anges 65 and 66 are clamped together,
II is prevented by abutment with the nozzle, as i with the gaskets between them to seal the joints,
‘will be clear from Fig. 2. When the nozzle is by a series of angularly spaced bolts 1i (Fig. 9).
removed from its support, lever 25 may be swung The ?ange 66 has a series (four as shown in Fig.
in a clockwise direction into vertical position to 5) of lugs 12 projecting outwardly beyond the
overlying ?ange 66 to receive the bolts 20', here
start the motor.
tofore described as securing the pumping unit to
The pumping unit has provisions for separat
ing from the gasoline any air that may be passed its supporting means I 9. It will thus be seen
that the lower casing 61 only is bolted to such
up pipe 29 and such air, and usually some gaso
line with it, is expelled through a pipe 40 which supporting means IS. The bolts 1i may be re
leads upwardly to a tank-like device 4|. This moved to enable removal of the motor including .
device, as shown in Fig. 3, affords within it a the lower head 56 and other parts later to be
chamber 44 into the upper part of which the air described, without removing the bolts 20, thereby 60
and gasoline is delivered. In this chamber the leaving the lower casing tightly bolted in place.
gasoline and air are gravitationally separated -The pipes 29, 30' and 40, being all the pipe con
and the air passes out to the atmosphere. In nections to the pumping unit, connect with the
detail, the air leaves through ports 45 formed in lower casing. Thus, the pumping unit, including
the upper wall of chamber 44, passing into an the motor and all parts driven therefrom and all 65
overlying ?oat chamber 46, from which the air parts housed in end plate 58, may be removed
escapes through an outlet 41 in the top wall of without breaking any pipe connections.
The lower casing 61 is formed to provide a cen
such chamber. A cap 49 covers outlet 41 and
70 contains a screen 46 through which the air must tral boss 13, into which the suction pipe 29 is
pass to reach the outlet 49' of cap‘ 49. The threaded and in which is a cylindrical passage 14, 70
outlet 41 can be closed by a valve 60 fixed to the upper end of which converges into an opening
a ?oat ii in chamber 46,.if and when necessary 15 of smaller diameter, forming the inlet eye of
the centrifugal pump. Casing 61 is also formed
because of some unusual and abnormal condi
76 tion, to prevent gasoline from passing out to provide a discharge chamber 16 of annular
form, encompassing the boss 13 and connected 76
thereto by a circular top wall 11 which extends
part way across the upper end of chamber 18 in
overhanging relation and through which the
, opening ‘I5 extends. The casing 81 is also formed
with an outlet ‘I8 (Fig. 10) for chamber 19 and in
to this outlet pipe 38 isthreaded. The lower wall
82 of end plate, 58 and the top wall ‘ll of the lower
casing together form the housing of a centrifugal
pump and are suitably recessed as shown, to form
10 a pump-chamber 19.‘ This chamber diminishes in
height from a maximum near the central opening
15 to a minimum at its outer peripheral part
where it converges to a very narrow outlet slot 88.
This slot, which forms a diffuser, extends entirely
16 around the chamber and communicates with the
underlying outlet chamber ‘I8 by a downwardly
curving slot M which diverges in the direction of
liquid flow. In the chamber 19 is located the im
pel1er82 of a centrifugal pump. The construction
of this impeller is such that it may be, and prefer
ably is formed by die casting. As shown, the im
peller is of the open type. It has a central hub 83
keyed to the lower end of the armature shaft 88 of
motor 2| and clamped against a shoulder 85 on
said shaft by a nut 86. Integral with the hub 83
confusion in Fig. 4). The inlet port 89 lies inside
this groove and ?ange and directly communicates
with said central area. Particularly, the port 99 -
directly overlies the impeller 82 of .the centrifugal
pump at a radial location which is close enough to
the axis‘ thereof to receive all the air and gases
collected in the suction pipe as will appear. The
outlet port 98 communicates with an overlying re
cess I88, formed in hub 83 and from which a pas
sage I8I extends radially outward through one of
the webs 88 (Figs. 4 and 9) to the periphery of
end plate 58,-the outer end of this passage being
closed by a plug I82. Communicating at one end
with passage IIII is a passage I83 which extends
downwardly to and through ?ange '65 and regis 15
ters with a passage I88 which extends from the
upper surface of ?ange 86 downwardly to a lateral
outlet passage I85, formed in the base member 61
and connnected to the described pipe 88.
The innner rotor 9| of the displacement pump 20
is driven in the direction of the arrow shown in.
Fig. 7 by the motor on the shaft 98 of which it is
‘mounted. The rotor 9| in turn rotates the outer
and annular rotor about the axis 93. The inner
rotor has one less tooth than the outer rotor and 25
is a disc 81 having a fiat upper face and a lower ' the contours of the teeth and the spaces between
face of frusto-conical form. Depending from this them are designed so that the teeth of each con
tinuously slide in close contact over the contour of
lower face are a series of angularly-spaced im
peller vanes 88 the inner ends of which are spaced the other. In the priming pump the teeth of one
rotor are generated by the teeth of the other rotor. 30
from hub 83. Formed in disc 81 between the in
ner ends of vanes 88 and hub 83 are a series of The two rotors present a series of closed pockets
I88 which gradually expand in volume as the ro
vertical holes 89. These holes enable ?uids, in
cluding all the air and gases in or with the volatile tors turn from the full mesh position I81 to the
liquid and normally also some of the liquid itself, open mesh position I81’ and then gradually con
tract in volume, as the rotors turn from the last 35
to pass‘vertically upward to an overlying displace
ment pump. These holes 89 open into a central named position back to the position I81. I prefer
area above the impeller, which area is partitioned to make this displacement pump according to the
principles of rotor construction used in either of
off from the remaining area by an upstanding an
the Hill Patents No. 1,682,564 and No. 1,682,565
nular flange or collar 89' formed on the im
of Aug. 28, 1928. During part of the time while 40
these pockets are expanding in volume they com
The displacement pump is desirably located im
municate with the inlet port»99 and thus, due to
mediately above the centrifugal pump in a cylin
drical chamber 98 formed in the lower portion of the suction created by the increase in volume of
hub 83 and opening into the aforesaid central area these pockets, fluid is drawn up through the port
of the chamber ‘I9 of the centrifugal pump. While 99 to ?ll the pockets. Then each pocket becomes 45
various forms of displacement pumps may be successively cut off from port 99 and shortly after
used for the purpose, it is preferred to use the moves into position where it can communicate
particular form of pump shown in Fig. 7. Such with outlet port 98. Then as the pockets I86
pump comprises a pinion gear 9|, keyed to the gradually decrease in volume, the fluid is ex
pressed through the port 98 into the outlet pas 50
shaft 88 of motor 2 I, and an annular gear 92, ro
60 tating about an axis 93, eccentric to shaft 88. The sages above described.
A modi?cation in the shape of the inlet port is
annular gear turns in a cylindrical recess formed
in a center plate 98 concentric with axis 93. Plate shown in Fig. 11 at 99’. The boundary walls of
98 is clamped between two end plates 95 and 98 this port, instead of being vertical are inclined to v
the vertical and approximate a helix. The ?uid 55
through which shaft 88 passes with ample clear
whirling in the pump chamber in the direction of
ance, as indicated. The provision of this clear
ance is for the purpose of avoiding the wear on the arrow shown in Fig. 11, enters the port in a
the shaft 98 which would otherwise occur if it more natural and smoother manner. The kinetic
made contact with these plates which, because of energy of the ?uid is to some degree utilized to \
the nature of the pump, have to be hardened and cause it to enter the inlet port 99' rather than re 60
lapped to engage with an exceedingly close fit the lying solely on the partial vacuum created by the
end faces of the gears 9| and 92. A series of cap displacement pump.
Above the displacement ‘pump, the hub 83 is
. screws 91 pass through the plates 98, 95 and 96
bored out to receive an anti-friction bearing. Be
and thread into hub 63 to fasten the displace
cause of the exceedingly close clearances between 65
65 ment pump in place. In addition, other screws the rotors of the displacement pump, it is essen
91' pass through plates 96 and 98 and thread into
tial that the motor shaft 88 be held in very close
plate 95 to clamp the plates together and main
alignment. An ordinary sleeve bearing such as
tain the parts of the displacement pump in as
sembled relation when the screws 91 are removed. is ordinarily supplied in electric motors would
not sumce because the usual clearance of one to 70
70 The plate 95 is formed with an outlet port v98 of two thousandths of an inch would allow too great
the form shown in Figs. 4 and 6 and the plate 96
is formed with an inlet port 99 of the form shown an eccentricity of movement of the shaft for the
closely inter?tting rotors. By preference, of the
in Figs. 4 and 8. The plate 96 is recessed to rotat
ably receive the ?ange 89' (see Fig. 12 where this various forms of bearings available, a ball bearing
arrangement has been separately shown to avoid having the inner and outer races I88 and I 89 75
with intervening balls III, is employed to secure
a mounting of the shaft which will hold it with
the close degree of accuracy required in the in
tended alignment. For similar reasons, the dis
placement pump is located as closely as possible
to the bearing and the impeller of the centrifugal
pump is located as closely as possible to the dis
placement pump. The overhang of the shaft be
low the bearing is made as short as is feasible to
10 avoid the possibility of any eccentric movement
of the shaft due to whipping or centrifugal action.
Actually, the bearing ‘and the displacement
pump are spaced because of the necessity of pro
viding a sealing means to prevent escape of gas
oline from the displacement pump around the
shaft 84. Such means is mounted in a cylindri
cal chamber III, formed within a tube II2 which
extends between plate I4 and the race I“. The
sealing means comprises a cup-shaped metallic
member III having an opening in itsend face
through which shaft 24 passes, and within the
cup portion a packing washer II4 tightly ?tting
the shaft. A spring Ill acting between the race
I" and the washer II4, presses the latter against
trifugal pump be of the particular form shown,
viz., the two closely spaced annular walls with
the narrow slot ll therebetween. Instead of that
type of diffuser, I may use any other suitable
type such, for example, as that shown in Figs.
13 and 14. The diifuser in this case comprises
a circular series of angularly spaced vanes I20,
surrounding the impeller and mounted between
the upper and lower vertically-spaced parallel
walls I M ‘and I22, being ?xed to or integral with 10
one of-such walls. These walls, it will be noted,
are more widely spaced than the corresponding
walls in Fig.4. This enables a substantial reduc
tion in the friction loss to be effected. These
vanes I 20 a?'ord between them specially shaped 15
passages I23 which gradually enlarge in the
direction of the flow of liquid through them and
which function to gradually reduce the velocity
of the-liquid leaving the impeller and to e?lciently
transform the kinetic energy of the liquid into 20
pressure energy. This form of diffuser, like the
former, avoids the dissipation in- eddies of the
kinetic energy of the liquid and avoids cavitation,
but .it accomplishes these results with less of a
the bottom of the cup and presses the .outer end friction loss.
face. of the cup against the lapped upper face of
This form of di?'user is, however, not widely
pump plate I‘. The cup III is caused to turn ' used
for relatively small centrifugal pumps be
with shaft 44 because of the frictional engage
cause it is di?icult and expensive to accurately
ment of the washer with both cup and shaft. The form and finish the vanes, which due to space
spring I'll turns with shaft 24 since it presses at limitations have to be very small. These dis
one end against the race IIII ‘which-is ?xed on advantages, I overcome by forming the vanes by 80
the shaft, and at the other end against washer die casting. The vanes are integral parts of a
II4 which also is ?xed to the shaft.
removable plate secured to one or the other of
The chamber which houses the sealing means is the castings 58 or 81. While these castings 58
vented by a radial passage II! formed in one of
or 61 do not lend themselves to manufacture by
the radial webs 84 and extending from tube “2 die
casting, a small section such as shown in
outward to the periphery of end plate II for com-‘ Figs. 13 and 14; may readily be die cast. In this
munication with the atmosphere. An annular case,
I have provided two die cast plates I24 and
groove I I1 is formed in the outer periphery of I2! which
line the inner, and confronting faces
40 tube H2 and communIcatesAwith passage IIt‘and
of the castings 58 and i1 and which are suit
, a plurality of radial holes III are provided in
ably held thereto as by screws I26 and I21, re 40
the tube to enable'oommunication between its spectively. The plate I24 carries the vanes I20.
interior and groove III. This venting, means These plates between them form the walls of the
provides an easy path for the escape of in?amma
pump chamber ‘It, the walls HI and I22, the dif
45 ble vapors should any such leak from the dis
with its vanes I20 and intervening passages
placement pump. Except for this means, the fuser
I22 and the outlet passage OI. All the surfaces 45
vapor might, in the event of leakage, creep along of
these elements may be formed with close ac
the shaft, entering the casing ofmotor 2I and curacy
by die casting, thus eliminating much
the housing 22' of the motor switch, and be ex
expensive machining. The castings 58 and 61
ploded by an electric are from the switch.
_ are machined to receive the plates I24 and I25,
Above the ball bearing described, there is a respectively, but the machining
required is sim 50
portion “9 formed on the upper part of hub 63 ply plain facing and boring. The difficult sur
and such portion appearslike an ordinary sleeve
faces to machine, including the curved surfaces
- bearing, encompassing the shaft with a fit com
parable to that used in a sleeve bearing. This and the tapered surfaces, are formed accurately
portion II. is provided as a safeguard in the and at low'cost by die casting. As heretofore 55
event that an explosion should occur inside the noted, the impeller also may be formed by die
motor casing. The purpose of portion I I! is to casting. Aside from the saving in cost, which is
important, all the surfaces exposed to the liq
prevent flame from penetrating into the displace
are formed with a smooth and polished ?n
ment pump and causing an explosion there. The
portion II 2 thus serves as a ?ame arrester and ish, which results in a material reduction of the' 60
friction loss and a material increase in the effi
not in any sense as a bearing for shaft 04.
The motor 2I may have both bearings for shaft ciency of the pump. To secure polished surfaces
04 constructed as described. It is not, however, formed with close accuracy, with the construc
essential that the upper bearing be so constructed. tion shown in Fig. 4, would require a large
That is. a small radial play between the shaft and amount of time and expert hand labor.
The operation of the apparatus will now be
upper bearing of an amount within the usual
tolerances of ‘a sleeve bearing will cause no diffi
accomplished in the usual way. The operator
culty. The small play in the upper bearing re
70 sults in a greatly reduced play of the shaft at removes nozzle 28 from support 39, moves lever
the point where the rotor OI is attached to it 25 in a clockwise direction (Fig. l) to close the 70
switch of motor 2I and thus‘ start the pump in >
because the length of the shaft between the bear
operation. He then inserts the nozzle in the
ings is several times the length of the shaft be
tank to be. ?lled and controls the ?ow with the
tween the lower bearing and rotor 2|.
nozzle valve, closing it when the register 32 of
It is not essential that the diffuser for the cen-' the meter shows that the desired quantity has
been delivered. He then replaces the nomle on
is directed axially toward the same and in a
' , its support and moves lever 25 to stop the motor. manner such as to enable the whirling effect
When the apparatus is ?rst installed, it will a of that pump to be carried down into the suc- ‘
be necessary to drive all air out of the system
and this is accomplished by operation of the
_ pumping unit with 'the valve of nozzle 88 held
open. The displacement pump alone first func
tions in this operation, pumping out air and dis
charging it through pipe 48 to chamber ‘44 and
.10 then to the atmosphere until liquid has been
tion pipe and form a vortex. The liquid, being
heavier, is thrown outwardly while the air is
.forced radially inward toward the center of the
vortex. The displacement pump scavenges this
vortex, removing air and gases therefrom, when
ever present, and with them some liquid and at
other times liquid only, and discharging the
same to ‘the liquid recovery chamber 44. Here
the impeller blades 88. Then the centrifugal the air escapes to the atmosphere and the liq
pump becomes active and forces liquid up pipe fuid is collected and returned from time to time,
88, driving the air ahead of it until the meter by way of pipe 51 to the suction pipe. The
15 3|, pipe 34, indicator 36 and the hose are entirely holes 89 enable the air and gases which cling
?lled with liquid. Then the valve of nozzle 88 as closely as possible to the hub 83 of the im
is closed and the system ‘is ready for the normal peller, to rise directly into the overlying inlet
- ‘ drawn up in suction pipe 29 far enough to reach
port 89 of the displacement pump. This path
Once the system is thus ?lled, this air-elimi
hating operation will not ordinarily need to be
repeated.v The foot valve or check valve asso
ciated with the suction pipe 29 will,_ if it closes
tightly, maintain the pipe ?lled with liquid and
the centrifugal pump primed. . However, if and
when this valve leaks, making priming of the
centrifugal pump necessary, the work will be ac
of escape isthus the direct and natural one for
air and gases which tend to rise._ At'the same
time, the annular ?ange 88' which is preferably
employed as described, prevents any possibility
of a circulation of liquid around the impeller,
as from the tips of blades 88 over the top of
the plate 81 to holes 89 and thence downwardly
to the inner ends of the blades 88. Such a cir
culation, involving as it does passage of‘ ?uid
complished quickly and automatically by the dis
placement pump with a minimum of effort. This through holes 89 in a direction opposed to the
follows because the system on the discharge side planned direction of air ?ow through these holes,
30 of the centrifugal pump remains completely would interfere with- the smooth operation of 80
?lled with liquid. The discharge chamber 18 of ‘ the displacement pump in its work of air re
the centrifugal pump is below the level of the moval. As it is, there are two separate and nat
ural paths, one for liquid to the impeller blades
chamber 19 of that pump and consequently liq
uid does not drain back from the‘discharge side of the centrifugal pump and one for air and gases
the pump to the suction pipe 29,--the nozzle to the rotors of the displacement pump. Since
w of
38 being closed and there being no other way the latter has a capacity great enough to remove
for'air to enter the discharge line. Thus, when all air. from suction pipe 29, it will naturally be
priming of the centrifugal pump is required, it more than su?icientto; remove all the air and
is only necessary to 'exhaust the air from the gases that travel up pipe 29 in or with the liquid,
chamber 19 of that pump and from the suction in the normal operation of the apparatus. Air
pipe 29. This is an important feature because and gases will thus be held within the central
area of the impeller inside its blades and be
it enables the priming, to be quickly accom
plished. It would be much slower if air had also kept from reaching ,said blades and passing to
to be exhausted from the discharge line because the discharge line and meter. Thus air-free liq
uid only can reach the meter.
45 the air expands during the exhausting process '
Actually, considerable liquid will be discharged
and it takes a long time to remove it all. If the
system could completely drain, one would be by the displacement pump and later returned to
obliged to repeat the operation used when the the suction pipe.‘ However, little energy is re
pump was ?rst installed, and continual adjust- , quired for this work because the pressure de
ments of the meter readings would be necessary, veloped by the displacement pump is only that
or corrections made to compensate for operation small amount necessary to‘ raise the ?uids the
small distance to the chamber 44 which is al
of the meter by air. So it is important, in or
ways vented to ‘the atmosphere. Heretofore,
.der to avoid making such adjustments or cor
where separation has been accomplished ‘in an
rections, to keep the discharge side of the sys
accessory device, it has been necessary to raise
tem completely‘ ?lled with air-free liquid.
In the normal operation, on the closing of the all the liquid which is by-passed through the
separator back to the suction line, to a substan
switch of motor 2|, both pumps are simultane
ously setin operation and, if the impeller blades
88 are submerged in liquid, the centrifugal pump
tial pressure-usually to the operating pressure
of the pump (generally at least 15 lbs. per sq. in.) .
immediately begins its work. If not, the opera
This requires‘ considerable work and represents
tion of the displacement‘pump will soon raise
liquid to the elevation necessary for the purpose.
The centrifugal pump not only supplies the nec
essary pressure to force the liquid through the
discharge pipe, meter, hose and nozzle, but it also
enables a very e?icient separation of air and
gases from the liquid to be effected under all
a substantial waste of energy. In some cases,
as much as 15 per cent of the pump liquid, which
conditions,. irrespective of the amount of air
and the viscosity of the liquid. The air-separat
70 ing function takes place in the following man
ner. The impeller blades 88 whirl the liquid
at a' very rapid rate (say for, example 3500
R. P. M.) and this whirling of the liquid ex
tends far down into. the suction pipe.
76 pipe, at least at its inlet to the centrifugal pump,
has been raised to the heavy operating pressure,
is by-passed back to the suction line. In the
present case, a substantially less volume, say
10 per cent, is thus by-passed but none of this
liquid is raised to the operating pressure of the
pump nor indeed to any appreciable pressure at
all. So the work of the displacement pump does
not consume much energy.
The plan of air separation described does not
require for its success any back pressure, as
does the ordinary air separator used in gasoline
dispensing systems as an. accessory.
In such
systems, a check valve, usually opening only aft 78
er at least ?ve pounds pressure has been built
up at the hose nozzle II, is used. The use of
such a valve means that additional pressure must
be built up by the pump and more power con-»
5 sumed in doing it. Actually, no such valve is
required for the air separating function described.
It is simply necessary to whirl the liquid by the
centrifugal pump and allow the vortex to form
as described. However, to prevent draining of
10 the hose when the apparatus is not in use, I
use some sort of a valve at the nozzle 36 which
valve can only be opened when pressure exists
there but the pressure may be much less than
that usually employed.
And by reducing the
15 back pressure due to this nozzle valve, the op
erating pressure can be reduced by the same
amount and a substantialsaving, around 20 per
cent, made in the size of the motor and the
power consumed. ,A smaller and thus cheaper
motor may be used than can be in the usual
meter-type gasoline dispensing apparatus, as
suming equal volume of delivery in a given time
in each case.
The centrifugal pump is utilized solely for
pumping the liquid to be measured and then dis
pensed. No part of this liquid, which has to
be raised to a substantial pressure, is returned
to the suction line, as is usual. Thus‘, less power
is required to operate it. Also, the motor 2|
need not have a high starting torque as is nec
essary where displacement pumps are used. The
centrifugal pump builds up pressure gradually
although in ample time for the purpose,—that
is in the interval during which the operator,
after having removed nozzle 36 from its support
I! and turned on the motor switch, carries
the nozzle to the tank to be ?lled. The particu
as is the fact, air-free gasoline made foamy in
appearance because of bubbles of partially-va
porized gasoline. The diffuser which may be of
the form shown in Fig.‘ 4 or the vane type shown
in Figs. 13 and 14, prevents the dissipation in
eddies of the kinetic energy imparted to the
gasoline by the impeller, and prevents cavita
tion. By the use of the di?'user, the velocity of
the liquid discharged by the impeller is reduced
gradually and without shock to the velocity of
the liquid in the discharge pipe. The necessary
conversion of kinetic energy into pressure energy
is effected smoothly and efficiently, without the
formation of eddies-resulting in a high pump
ing e?lciency. The pressure is maintained more 15
nearly uniform, irrespective of rate of delivery,
over a considerable range. While it is important
and desirable to secure the e?lciency of pump
ing, the really necessary and critical thing is to
so discharge the liquid that it will not have the
objectionable milky or foamy appearance and
this is secured by the use of a diffuser.
It is to be noted that the action of the centrif
ugal pump in whirling the liquid, removes any
particles of foreign matter which may be carried
in suspension in the liquid, out'of the inlet path
to the displacement pump. The latter is thus
protected against the entry of foreign matter
which might, because of the closely ?tting parts,
interfere with its operation or cause undue wear
of the parts. The displacement pump is only
required to pump clean liquid and air or gases.
The allusion to foreign matter has reference to
the very ?ne particles that are almost always
present and are carried in suspension in the
liquid and are so ?ne that they are not removed
lar type of centrifugal pump illustrated has the ' by the screens or ?lters usually connected some
where in the suction line to the pumping unit.
advantage of maintaining a substantially uni
form pressure, irrespective of the rate of liquid There are no substantial quantities of solids en
delivery, over a considerable range. Unlike other
pumps of this general class, the pressure does
not fall oi! sharply as the rate of delivery of
liquid increases. For example, with the present
pump, the pressure remains substantially con
stant for all rates of delivery up to 16 gallons
per minute. Another advantage of the centri
fugal pump is that no by-pass valve need be
used with it to prevent building up excessive
pressures in the discharge line when the pump
is operated, as it often is, while the valve of
the hose nozzle 36 is closed. At such times, the
impeller of the centrifugal pump simply churns
the liquid around‘ in the pump chamber 19.
The particular type of centrifugal pump illus
trated has a special advantage in a dispensing
apparatus for gasoline and other relatively vola
tile liquids. It is not enough merely to pump the
gasoline in the same way that water or other
less volatile liquids are pumped bymfugal
pumps of ordinary form. For the special use
described,‘ the pump must be designed to avoid
cavitation and the formation of eddies in the
discharge chamber. Without a suitable di?’user
cavitation can occur‘ there and the liquid leav
ing the impeller will whirl around at high veloc
"ity in an area “reduced-pressure. Partial va
porization of the gasoline may occur under cer
tain conditions, depending on the vapor pressure
10 of the liquid, its temperature and pressure; and
. \the liquid delivered, as shown in the sight glass
indicator 3|, would have a vfoamy or milky ap
pearance which is decidedly objectionable in the
“trade. The ‘customer, seeing bubbles in the
7‘ liquid, assumes them to be air bubbles and not,
tering this unit and the foreign matter, referred
to, passes throughthe centrifugal pump and out
:he discharge line as in other dispensing sys
The motor-driven pumping unit is designed to
enable substantial savings to be effected in cost
of manufacture over the apparatus heretofore
used to do the equivalent work. The two pumps
are directly connected to the shaft of the driving
motor and are housed in a casing which includes
as one element a special end plate for the mo
tor,—thus affording a very compact arrange
ment. Separate mountings for the pumps and
driving connections between each pump and the
motor are dispensed with and the air separator
accessory is no longer necessary since its work is
accomplished in the pumping unit. Additional
savings in cost can be effected by the use of the
die-cast linings for the centrifugal pump shown
in Figs. 13 and 14.
The construction is also such that there are
few moving parts and few parts to wear andre
quire servicing in the ?eld. However, such serv
icing ‘is readily accomplished when required.
One simply removes the bolts ‘II, after the elec
trical connections to motor 2| have been broken,
after which the motor, displacement pump and
the moving part of the centrifugal pump can be
removed as one unit. No breaking of pipe con
nections is required and the work can be per
formed with only a very short interruption in the 70
use of the apparatus, especially if. as is often the
case, a new unit is substituted for the old one
and the latter sent ‘to the factory for recondi
tioning. 'Ihe displacement pump, however, is
made as a separate unit and can be readily re 78
moved (by simply removing the impeller 81 and
cap screws 91) and a new vunit substituted.
In ' ing a passage forming a continuation of said
case the die-cast construction of Figs. 13 and 14s
is used, it will also be ‘necessary to remove screws
I26 and plate I24.’ The centrifugal pump in
volving only the one moving part which is not
subject to wear, should require no servicing.‘ It
will be seen that the design is such as to reduce
to extreme simplicity the operation of servicing
10 and inspection.
servicing the'apparatus in the ?eld. It also re
15 sults in much smoother and quiet operation. Its
use in a meter type gasoline dispensing appa
ratus enables air, and gases to be separated from
the liquid under all conditions regardless of the
amount of air and the viscosity of the liquid,
without the use of any additional apparatus for
‘the purpose, and insures that air-free liquid
only will be delivered ‘to and measured by the
meter and that the air-free liquid discharged
will have a clear appearance and be free from
What I claim is:
1. In apparatus ofnthe class described, an elec
tric motor including its shaft and the end plates
in which‘ said shaft is rotatably mounted, a cas
30 ing secured to one said end plate, such plate and
casing forming between them a centrifugal pump
chamber, said last named end plate having a
recess therein adjacent said chamber, a displace
ment pump mounted in said recess and having
a rotatable member ?xed to said shaft, and a
centrifugal pump impeller located in said cham-‘
her and ?xed to said shaft, said casing having
therein an inlet for the centrifugal pump and
outlets one for each pump, the displacement
40 pump having its inlet in direct communication
with said chamber.
outlet passage and terminating with a port for
connection to an outlet pipe, all constructed and
arranged so that the motor with, the displace
ment pump and said impeller may be removed as
one unit leaving said casing connected to said
several pipes.
4. In apparatus of the class described, an elec
, tric motor including its shaft and upper and 10
The invention thus affords by the use of the
composite pumping unit described, substantial
savings in manufacturing cost and in the cost of
passage extending to said casing, said casing hav
2. In apparatus of the class described, an elec
tric motor including its shaft and the end plates
in which said shaft is rotatably mounted, a casing
45 secured to 'one said end plate, such plate and
casing forming between them a centrifugal pump
chamber, said last named end plate having a re
cess therein adjacent said chamber, a displace
ment pump mounted in said recess for removal
50 and replacement as one unit and having a rotat
able member ?xed to said shaft, and a centri
fugal pump impeller located in said chamber and
?xed to said shaft, said casing having therein
an inlet for the centrifugal pump and outlets one
55 for each pump, the displacement pump having
its inlet in direct communication with said chain-'
3. In'apparatus of the class described, an elec
tric motor including its shaft and its end plates
60 in which said shaft is mounted, one said- end
plate having a central recess in its outer face
‘encompassing said shaft, a displacement pump
mounted in said, recess and having a rotatable
member ‘?xed to said shaft, a casing secured to
the last-named end plate and cooperating with
‘ it to form a centrifugal .pump chamber, a cen
lower end plates in which said shaft is mounted
with its axis vertically ‘disposed, the lower end
plate having a centralrecess in its lower face en
compassing said shaft, a displacement pump
mounted in said recess for removal and replace 15
ment as one unit and having a rotatable member
?xed to said shaft, a casing secured to the lower
end plate and cooperating with it to form a cen
trifugal pump chamber, a centrifugal pump im
peller located in- said chamber and fixed to said 20
shaft, said casing having an inlet passage adapted
for connection to an inlet pipe and extending ax
ially to said chamber and a peripheral outlet
passage leading from the chamber and adapted
for connection to an outlet pipe, the inlet port 25
of the displacement pump overlying and com
municating with said chamber, said lower end
plate having an outlet passage extending to said
casing, said casing having a passage forming a
continuation of said outlet passage and termi 80
nating with a port for connection to an outlet
pipe, and a ?xed support for said casing, all
constructed and arranged so that the motor with
the displacement pump and said impeller may be
removed as one unit leaving said casing on its 35
?xed support and connected to said several pipes.
5. In apparatus of the class described, an elec
tric motor including its shaft and the end plates
in which said shaft is rotatably mounted, a casing
secured to one said end plate, such plate and 40
easing forming between them a centrifugal pump
chamber, said last-named end plate having a
recess therein adjacent said chamber, a displace
ment pump mounted in said recess and having a
rotatable member fixed to said shaft, 2, centrif 45
ugal pump impeller located in said chamber and
?xed to said shaft, said last-named end plate hav
ing a bearing for said shaft axially spaced from
the displacement pump and located on the opposite
side thereof from said impeller, said last-named 50
end plate having a chamber between the dis
placement pump and one side of said bearing,
a seal ring mounted on said shaft in said last
named chamber and engaging the adjacent face
of the displacement pump, said last-named end 55
plate having a‘ vent passage leading from said
last-named chamber to the atmosphere for the
escape of any in?ammable vapors which may
pass said seal ring and having also on the op
posite side of said bearing a ?ame arrester en 60
compassing said shaft and preventing the trans
mission of ?ame from within the motor along
said shaft and through said bearing into said
' last-named chamber.
6. Pumping apparatus, comprising, a centrif
ugal pump impeller having a member carrying on
trifugal pump impeller located in said chamber
and ?xed to said shaft, said casing having an
one face thereof a plurality of vanes and on the
inlet passage adapted for connection to an inlet
?rst and second casing sections one on each side
70 pipe and extending axially to said chamber and
a peripheral outlet passage leading from the
chamber and adapted for connection to an outlet
pipe, the inlet port of the displacement pump
lying adjacent and communicating with said
75 chamber, said last-named plate having an outlet
opposite face an axially directed annular collar,
of the impeller and secured together and form 70
ing between them a chamber to enclose the im
peller, a drive shaft mounted in the first section
and extending through said collar in spaced con
centrical relation and being secured to said im
peller, said first section having in its inner face 75
a recess opening into said chamber, a displace
ment pump mounted in said recess and driven
from said shalt, a die-cast plate inset into and
covering the inner face oi the ?rst section and
closing said recess except for a central opening
through which said collar extends, said mem
ber having air passages through it .close to the
axis and inside said collar, the second section
having inlet and outlet passages for said pump
chamber and cooperating with said die-cast plate
to form the pump chamber and a di?'user con
necting the pump chamber to the outlet passage.
'7. Pumping apparatus, comprising, a centrif
ugal pump impeller having a member carrying
15 on one lace thereof a plurality of vanes and on
the opposite lace an axially ‘directed annular
collar, ?rst and second casing sections one on
each. side of the impeller and secured together
section and extending through said collar in
spaced concentrical relation and being secured to
said impeller, said ?rst section having in its inner
face a recess opening into said chamber, a dis
placement pump mounted
driven from said shalt, a
into and covering the inner
tion and closing said recess
in said recess and
die-cast plate inset
face of the ?rst sec
except for a central
opening through which said collar extends, said
member having air passages through it close to 10
the axis and inside said collar, the second sec
tion having inlet and outlet passages for said
'pum'p chamber and cooperating with said die-cast
plate to form the pump chamber'and a diil‘user'v
passage connecting the pump chamber to the
outlet passage, said plate having di?user vanes
extending in the di?user passage and abutting
the second named member.
and forming between them a chamber to enclose
20 the impeller, a. drive shaft mounted in the ?rst
Без категории
Размер файла
1 718 Кб
Пожаловаться на содержимое документа