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Патент USA US2105999

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2,105,999
Patented Jan. 18, 1938
UNITED srATEs2,105,999PATENT
OFFICE
PUMP STRUCTURE
James Moore Evans, Detroit, Mich, assignor, by
mesne assignments, to Grade Crossing Guard
Corporation, Memphis, Tenn., a corporation of
Tennessee
Application August 2, 1935, Serial No. 34,323
2 Claims. (01. 103-41)
The present invention relates to pumping
mechanism, and more particularly to pumping
mechanism‘ constructed to provide a positive ?ow
in one direction, and to permit a relatively free
flow in an opposite direction.
It is an object of the present invention to
provide a pump constructed to provide a positive
?uid ?ow in one direction, and to permit a rela
tively free ?uid flow in an opposite direction.
It is also an object of the present invention
10 to provide apump structure embodying a pump
chamber and selectively controllable means to
permit a relatively free flow of ?uid around the‘
pump chamber.
\
tively draw ?uid from the inlet chamber and
discharge it through the outlet chamber. In
order to permit a relatively free ?ow of ?uid
through the pump structure without passing
through the pump chamber, selectively controlled
valve mechanism is provided to complete an aux
iliary* connection between the inlet and outlet
chambers. 'As illustrated, the inlet and outlet
chambers are provided with a common separating
wall, and‘ the valve mechanism is positioned to
open and close a port provided in such common
separating wall.
0
.
The arrangement is preferably such that the
selectively controlled valve responds to the speed
of operation of the pump, being moved to a closed‘ 6
position when the pump is operating at or above
a predetermined rate, and being moved to an
chamber and automatically controlled mecha
‘nism to permit a relatively free ?ow of ?uid ' open position when the speed of operation is
It is also an object of the present invention
v15 to provide a pump structure embodying a p11‘ 1p
around the pump chamber.
'
It is also an object of the present invention
to provide a pump of the last mentioned char
acter in which the by-pass mechanism is re
sponsive to the speed of operation of the pump.
[It is also an object of the present invention
to provide a pump structure embodying a pump
' ing chamber, inlet and outlet chambers, and a
selectively controlled valve to control a by-pass
port between the inlet and outlet chambers.
It is also an object of the present invention
8
to provide a pump- structure embodying a pump ,
.
‘
In accordance with the present invention’ also,
the selectively controlled valve may be rendered
independent of the pressures within the inlet and
the outlet chambers. As illustrated, this rela
5
tionship is accomplished by arranging the struc
ture so that in any position of the valve, the
parts directly associated therewith are subjected
to equal and opposite components of the pres
eration of pump structures.
may be accomplished in various ways. As illus
Other objects and advantages of the present
invention appear in the following description
and in the appended claims.
valve is mounted for reciprocatory motion in an
0.
trated, a piston member rigidly connected to the
auxiliary cylinder formed in the pump structure.
The cylinder area on one side of the piston com
tion;
municates with one chamber, and the cylinder
area on the other side of the piston communicates
with the other chamber. The area presented by
the piston is equal to the area presented by the
valve when in closed position. In any position
of the valve, accordingly, the pressure in either
the line 2——2 of Fig. 1; and
chamber. exerts equal and opposite forces on the
ing numerals are used to designate corresponding
parts,
Figure 1 is a view in vertical, axial section in
an illustrative embodiment of the present inven
Fig. 2 is a view in vertical section taken along
Fig. 3 is a view taken along the line 3-3 of
50
drives the pump.
0
chamber, and embodying valve mechanism dis
posed‘in balanced relation to the pump pressures sures within the inlet and outlet chambers, re
to permit a ?ow through the pump independently ’ spectively.‘ With this arrangement, the valve is
balanced in any given position with respect to
of the pump chamber.
It is also an object of the present invention the inlet and outlet chamber pressures.
The balancing of the selectively controlled valve,
to generally improve the construction and op
In the drawing, throughout which correspond- .
4
below such predetermined value. As. illustrated,
the speed responsive control of the‘ selectively
controlled valve is eiiected by governor mecha
nism suitably driven by the mechanism which
respectivev valve faces.
The present invention also comprises an ar
.
In accordance with the-illustrated embodiment rangement for ‘providing forpressure relief with
of the present invention, the pump ‘structure in the pump structure. As illustrated,‘ a spring
comprises generally a pump chamber, an inlet _ pressed check valve is disposed to control a sec
Fig. 1.
chamber, and an outlet chamber.
The pump
55 chamber comprises rotating mechanism to posi
ond port in the above mentioned connecting wall.
As described more in detail hereinafter, the check:
0
hi
5
2
2,105,999
valve remains closed as long as the pressure with
in the_ outlet chamber is below a predetermined
value, and moves to an open position when they
pressure in such chamber reaches or exceeds such
predetermined value. The predetermined value
is conveniently adjustable.
64 by a pin ‘I6. Spring 18 is disposed to bias valve
58 to the right, as viewed in Fig. 1, to close open
ing 52. As_ long, however, as the speed of shaft
20, and. hence of the pump, is below a certain'
value, the centrifugal governor mechanism desig
nated generally 80, forces spring 10 to the left, in
Considering the above elements in more detail, - which position it actuates valve 58 to the open
and referring to Figures 1, 2 and 3, casing I0 is
formed to provide a pump chamber‘ 12, an inlet
10 chamber I 4, and an outlet chamber I6. A pump
rotor l8, eccentrically mounted in chamber l2
on a drive shaft 20,v and having a ~plurality of
pumping blades 22 pressed outwardly by a spring
24, draws ?uid from inlet chamber» l4 through
15 port 26, and forces it into outlet chamber l6 by
way of port 28. Chamber l4 communicates with
a suitable source of ?uid supply through opening
30, and chamber I 6 is provided with a suitable
outlet passage 32.
Shaft 20, which may be driven in any suitable
manner, is provided with a recessed section 2|
over which rotor I8 is ?tted. Spring 23 and plate
25 provide a somewhat resilient thrust bearing
for the end of shaft 28.
'
Pumping blades 22 are slidably ?tted in dia
metrically opposed recesses 21 formed in rotor l8.
Spring 24, which biased blades 22 outwardly into
engagement with the walls of chamber l2, passes
through openings formed in rotor l8 and shaft 28.
30
The common wall 34 which separates chambers
l4 and I6 is provided with an opening 36, which
is normally closed by a spring pressed release
valve designated generally 38. Valve 38 comprises
a head 40, slidably ?tted in a recess 42 formed in
casing ID; a shank 44 slidably ?tted in a sleeve
46 which is threaded into casing in and termi
nates in an external head 48; and a biasing spring
50 which surrounds shank 44 and bears against
a shoulder formed thereon and a similar shoulder
40 formed on sleeve 46. Rotation of head 48 inone
position. When the pump speed exceeds the pre
determined value, however, governor mechanism
80 is retired, and spring 18 is rendered effective 10
to close valve 58. As will be understood, the
above mentioned balanced condition of valve 58
permits the use of a relatively light and simple
actuating member, and the above mentioned pres
sure differential which exists when the valve is 15
closed, aids spring 18 in maintaining the valve
in the closed position.
'
Although governor mechanism 80 may be of
any conventional type arranged to function as
above described, it preferably comprises the sleeve 20
14, tightly ?tted on shaft 28; an auxiliary sleeve
84 slidably ?tted on sleeve 14 and having project~
ing shoulders disposed for engagement by the end
sections 82 of the two governor arms 86; a pair
of weights 88 connected to‘ arms 86 and slidably 25
positioned within a frame 98 which‘ serves to
guide the movements thereof and is tightly ?tted
on sleeve 14; and a pair of biasing springs 92,
disposed to engage pins 94 which pass-through
weights 88, and serve to bias the latter inward 30
ly. _As will be understood, upon rotation of shaft
28, governor 88 rotates correspondingly, and
weights 88 are centrifugally forced outwardly
within frame 90. ,This motion of weights 88
causes arms 86 to move‘ sleeve 84 to the right as 35
viewed in Fig. 1. In response to this spring 10
moves to the right, closing valve 58 and moving '
collar 96 to the right. If the speed of shaft 20
falls below a predetermined value, springs 82
force weights 88 inwardly, causing collar 96 to 40
direction or the othercauses sleeve 46 to move . move to the left.
inwardly or outwar‘dly with respect to casing l0,
elongating ‘or compressing spring'50 and corre
spondingly varying the contact pressure of valve
45 head 40. As will be understood, if the pressure in
chamber I6 exceeds the force exerted by spring 50,
valve 38 is forced open, permitting the fluid to
pass freely between chambers I4 and I6, through
' opening 36, without passing through pump cham
50 ber l2.
Wall 34 is also provided with a second opening
52, which affords communication between cham
bers l4 and IS. A valve 58, disposed to engage
the margins of opening 52 to close the latter, is
This action force's spring 10
to the left, re-opening valve 58.
/
With reference to the operation of the pump as
a unit, it will be understood that opening 88 com
municates with a. suitable source of ?uid supply,
and that opening 32 communicates with a suit
able discharge line. With pump rotor 58 at rest,
valve 58 occupies the open position as previ
ously described. Under these conditions, ?uid is
enabled to pass through the pump casing, by way
of opening 52, without passing through pump
chamber l2. This ?ow may be in either direc-'
tion through the pump. " In application of the
pump to reciprocatory systems, such for example
55 connected to a piston 68 by a central post 62.
as disclosed in the co-pending application of the
Piston 60 is slidably ?tted in a cylinder 54 formed ' present applicant, Serial No. 34,322, ?led August
on the interior of casing l0, axially concentric
with opening 52. A passage 56 connects chamber
2, 1935, and assignedto the same assignee as the
present application, in which a corresponding
I 6 and cylinder 54. The diameters of piston 68,
is utilized to actuate a hydraulic ram, the
to cylinder 54 and opening 52 vare the same, but it is pump
?ow of the ?uicl'is ordinarily in a direction op
noted that valve 58 is somewhat larger than the posite to that produced when the pump is in oper
opening 52. When the valve 58 is closed accord
ation. In such instances, opening 52 permits a
ingly a, predetermined pressure differential exists return movementhf the ?uid.
which urges it to the closed position. When the
If the pump is placed in operation, the rotation
65 valve 58 is open on the other hand the pressures
of rotor l8 and of blades 22 positively draws ?uid
on opposite sides thereof are substantially equal, from inletchamber l4 through pump chamber
and differ only by an amount which is caused by l2 into outlet chamber I 6. As long as the speed
the cross sectional area of rod 64.
of the pump remains below the previously men
The shank 64 of valve 58 extends through cas
tioned predetermined value, valve 58 remains
70 ing Ill and into the interior of a governor hous
open
the ?uid thus circulated passes be-. 70
ing 66, which is suitably secured to, casing ill by tweenso'that
chambers l4 and I 6 by way of opening 52,
studs 68. A spring 18, suitably secured to the and substantially no pressure is developed by the
interior of housing 66 by studs 12, surrounds a pump in either of the lines connected to inlet and
governor sleeve 14 which is tightly ?tted on shaft outlet openings 20 and 32. As will be understood,
20, and is connected at its upper end to shank valve 58 may be caused to close at any desired 75
3.
' 2,105,999
operating speed of the pump. The preferred
operating speed is approximately one-half of the
normal full operating speed'of the pump.
Upon closure of valve 58, the inlet and outlet
chambers l4 and ii are isolated from each other
except through pump chamber l2. Accordingly,
' the ?uid circulated through the pump is drawn
from the inlet passage and passes out through
the outlet passage, the pressure developed being
determined by the pump characteristics.
If the speed of the pump falls below the pre
determined value, governor mechanism 80 actu
ates valve 58 to the open position, permitting the
previously -mentioned circulation of the ?uid
15 within the pump. Upon the opening of valve 58,
the pressure developed by the pump in the line
connected to passages 30 and 32 falls to substan
tially zero. If the ?uid in these lines is subjected
to any reverse pressure, such reverse pressure re
sults in a, reverse flow of the ?uid through the
pump by way of opening 52.
If at any time during the operation of the
pump, the pressure within outlet chamber l6 ex
ceeds a predetermined value, relief valve 38 is
25 actuated to the open position, connecting inlet
and outlet chambers l4 and I6 respectively by
way of openings 36, again permitting a circula
tion of the ?uid within the pump.
’
Although a speci?c embodiment of the present
invention has been described,'it will be evident
that various modi?cations may be made in the
form, number and arrangement of parts with
out departing from the spirit or scope thereof.
The described embodiments, accordingly, are to
to de?ne separate inlet and outlet chambers dis
posed on opposite sides of the interior wall, a
rotary impeller in said casing for transmitting
?uid between said inlet and outlet chambers,
said impeller being provided with a shaft pro
jecting outwardly of said casing, said interior.
wall having an opening therein to form a by;
pass connection between said chambers, a valve
movably supported in said casing for opening and
closing said opening and having an operating 10
rod projecting outwardly of said casing, and a
speed responsive means on said shaft having an >
operating connection between the shaft and the
rod externally of the casing whereby said valve
will be closed upon attainment of predetermined 15
speed.
_
r
2. In a pumping mechanism, a casing provided
with outer enclosing walls and an interior wall
to de?ne separate inlet and outlet chambers
disposed on opposite sides of the interior wall,
a rotary impeller in said casing for transmitting
?uid between said inlet and outlet chambers,
said impeller being provided with a shaft pro
jecting outwardly of said casing, said interior
wall having an opening therein to form a by 25
pass connection between said chambers, alvalve
movably supported in said casing for opening
and closing said opening and having an oper
ating rod projecting outwardly of said casing,
means associated with said valve for subjecting 30
it when closed to a ?uid pressure differential
acting in a direction to hold it closed, and a
speed responsive means on said shaft‘ having an
operating connection between the shaft and the
rod externally of the casing whereby said valve 35
be considered in- an illustrative and not in a -'
will be closed upon attainment of'predetermined
limiting sense.
What is claimed is: '
1. In a pumping mechanism, a casing provided
with outer enclosing walls and an interior wall
speed. ‘
JAMES MOORE EVANS.
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