U.S. patent number 3,764,233 [Application Number 05/198,679] was granted by the patent office on 1973-10-09 for submersible motor-pump assembly.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Navy. Invention is credited to Alvah T. Strickland.
United States Patent |
3,764,233 |
Strickland |
October 9, 1973 |
SUBMERSIBLE MOTOR-PUMP ASSEMBLY
Abstract
A submersible motor-pump assembly including: a reservoir casing
which is pted to contain a hydraulic fluid; a hydraulic pump
mounted within the casing, the pump having an inlet which is
located within the casing and an outlet which is extended through
the casing; an electric motor for purposes of driving the
aforementioned hydraulic pump; and the casing having means for
equalizing the pressure within the casing with respect to ambient
pressure.
Inventors: |
Strickland; Alvah T. (Kailua,
HI) |
Assignee: |
The United States of America as
represented by the Secretary of the Navy (Washington,
DC)
|
Family
ID: |
22734351 |
Appl.
No.: |
05/198,679 |
Filed: |
November 15, 1971 |
Current U.S.
Class: |
417/414;
417/371 |
Current CPC
Class: |
F04B
17/03 (20130101); F04B 47/06 (20130101); F04D
13/10 (20130101) |
Current International
Class: |
F04B
17/03 (20060101); F04D 13/08 (20060101); F04D
13/06 (20060101); F04b 035/04 () |
Field of
Search: |
;417/360,371,410,414,422,902 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Husar; C. J.
Assistant Examiner: Smith; Leonard
Claims
I claim:
1. A submersible motor pump comprising:
a reservoir casing which is adapted to contain a hydraulic
fluid;
a pump of the type having a housing with a fluid intake and a fluid
outlet;
means mounting the pump in the casing with the fluid intake of the
pump positioned for intaking said hydraulic fluid from within the
casing;
conduit means connected to the outlet of the pump and extending
through said casing for discharging the hydraulic fluid exterior
the casing;
said casing having means for equalizing the pressure within the
casing with respect to ambient pressure, the equalizing means
including:
said casing having a port opening to ambient; and
a bladder for containing the liquid media, said bladder being
mounted in the casing so that ambient pressure is applied to the
exterior of the bladder;
said casing having an annular interior recess adjacent the exterior
of the bladder for providing a space for containing sea water
therebetween;
said casing having a cap mounted at each end thereof;
said conduit means extending the pump outlet through one of the
caps;
said casing being generally cylindrical;
said bladder being generally tubular;
means for sealing the ends of the bladder within the casing;
an electric motor of the type having a housing;
said electric motor being mounted in one end portion of the
cylindrical casing and the pump being mounted in the other end of
the portion;
means drivingly connecting the pump to the electric motor;
the electric motor end portion of the casing having a hydraulic
fluid inlet for receiving fluid to the assembly;
the assembly spaces for the motor, driving means, and pump being in
liquid communication with one another so that received fluid will
first cool the motor and then supply the pump;
a plate transversely mounted within the casing for supporting the
pump;
a combination mount disposed within the casing for supporting the
pump plate and the electric motor;
the connecting means between the electric motor and the pump being
located within the combination mount;
a removable end plate transversely mounted within the casing and
spaced from one of the electric motor plates;
said electric motor having brushes which are mounted on the end
plate and located within the space between the end plate and said
one of the electric motor plates; and
pin and socket means connecting the brushes to the electric
motor.
2. A submersible motor-pump assembly comprising:
a reservoir casing which is adapted to contain a hydraulic
fluid;
said reservoir casing having a pump chamber and a motor
chamber;
a pump of the type having a housing with a fluid intake and a fluid
outlet;
means mounting the pump in the pump chamber with the fluid intake
of the pump positioned for intaking said hydraulic fluid from
within the pump chamber;
conduit means connected to the outlet of the pump and extending
through said casing for discharging the hydraulic fluid exterior
the casing;
a bladder mounted in the pump chamber around the pump; and
said casing having a port which communicates ambient pressure with
the exterior of the bladder.
3. A submersible motor-pump assembly as claimed in claim 2
including:
said reservoir casing being elongated;
an electric motor of the type having a housing;
said electric motor being mounted in the motor chamber;
the motor chamber having a hydraulic fluid inlet for receiving
hydraulic fluid to the reservoir casing so as to supply the pump
and cool the electric motor.
4. A motor-pump assembly as claimed in claim 3 including;
said casing having a cap mounted at each end thereof; and
said conduit means extending the pump outlet through one of the
caps.
5. A motor-pump assembly as claimed in claim 3 including:
said casing being generally cylindrical;
said bladder being generally tubular; and
means for sealing the ends of the bladder within the pump
chamber.
6. A motor-pump assembly as claimed in claim 5 including:
said pump chamber having an annular interior recess adjacent the
exterior of the bladder for providing a space for containing sea
water therebetween.
7. A motor-pump assembly as claimed in claim 6 including:
a plate transversely mounted within the pump casing for supporting
the pump;
a combination mount disposed within the casing between the pump and
motor chambers for supporting the pump plate and the electric
motor; and
the connecting means between the electric motor and pump being a
flexible coupling which is located within the combination
mount.
8. A motor-pump assembly as claimed in claim 7 including:
a removable end plate transversely mounted within the motor chamber
and spaced from one of the electric motor plates;
the electric motor having brushes which are mounted on the end
plate and located within the space between the end plate and said
one of the electric motor plates; and
pin and socket means connecting the brushes to the electric
motor,
whereby the brushes can be removed with the end plate for
inspection and then easily reconnected to the electric motor.
Description
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or
for the Government of the United States of America for governmental
purposes without the payment of any royalties thereon or
therefor.
BACKGROUND OF THE INVENTION
The old method of providing power to submersible systems involved
only the conversion of d-c electric energy to mechanical energy
with no hydraulic intermediary step. With such an arrangement
propellers on the submersible were driven directly by electric
motors. A disadvantage of this prior art approach is the high cost
of d-c submersible electric motors and electronic motor
controllers. Also, electronic motor controllers have not
demonstrated a high reliability when exposed to ocean
pressures.
In reviewing prior art systems which convert d-c electric energy
into mechanical energy in the form of high pressure hydraulic oil,
one is faced with bulky designs which would not be satisfactory for
many deep submersible vehicles. In U. S. Pat. No. 3,434,443 there
is disclosed a buoyancy transport vehicle which is operated by a
diver and must be compact in order to carry out its intended
purposes. This vehicle required a power unit which would utilize
battery power to provide hydraulic fluid under pressure for driving
various thrusters on the vehicle.
SUMMARY OF THE INVENTION
The present invention provides a very compact and streamlined power
unit which will operate at deep ocean depths to convert d-c battery
power to mechanical energy in the form of high pressure hydraulic
fluid. This has been accomplished by providing a submersible
motor-pump assembly which includes: a reservoir casing which is
adapted to contain a hydraulic fluid; a pump mounted within the
casing, the pump having an inlet which is located within the casing
and an outlet which is extended through the casing; an electric
motor for driving the pump; and the casing having means for
equalizing the pressure within the casing with respect to ambient
pressure. With such an arrangement the casing may be cylindrical
and of thin wall light weight construction.
STATEMENT OF THE OBJECTS OF INVENTION
An object of the present invention is to provide a compact and
reliable power unit which will convert d-c electric energy into
mechanical energy in the form of high pressure liquid media.
Another object is to provide a low cost, low weight, compact, deep
submersible power unit which is easy to disassemble and maintain,
not effected by depth of pressure, and low in noise level.
Other objects and many of the attendant advantages of this
invention will be readily appreciated as it becomes better
understood by reference to the description and accompanying
drawings which follow.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a longitudinal cross sectional view of the submersible
motor-pump assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing there is shown in FIG. 1 a submersible
motor-pump assembly 10 which includes a reservoir casing 12 which
is adapted to contain a hydraulic fluid 14, such as MIL-H-5606
hydraulic oil. A pump 16 with its own housing is mounted within the
casing and has an intake 18 which is located within the casing and
an outlet 20 which is extended through the casing by any suitable
means such as pipe 22.
An electric motor 24, preferably a d-c electric motor is mounted
within the casing 12 for driving the pump 16. The motor 24 is
drivingly connected to the pump 16 by a flexible coupling 26 and
has its own housing.
The casing 12 has means for equalizing the pressure within the
casing with respect to the ambient ocean pressure. This equalizing
means may include the casing 12 having a port 31 which opens to the
ambient ocean environment, and the bladder being mounted in the
casing 12 so that ambient pressure is applied to the exterior of
the bladder. In the preferred embodiment, the bladder 30 is
coextensive with the pump 16 and its appurtenances, to be described
hereinafter, since the pump intakes hydraulic oil within this area.
In order to establish pump pressure at a selected level above
ambient the pump may be provided with a compensator 32 which is
also located within the bladder area.
The pump 16 may be supported within the casing 12 by a plate 34
which is transversely mounted within the casing 12. The plate 34 in
combination with a plate 36 and an annular ring 38 adjacent the
plate 36 may comprise a means for sealing the ends of the bladder
30 about the pump 16 and compensator 32. The plate 34 is in turn
mounted to a combination mount 40 to which the electric motor 24
may also be mounted. A plate 42 may act as an axial alignment guide
for the motor field as well as a mounting bracket for electric
sockets 43. A space may be provided within the combination mount 40
for the mounting of the flexible coupling 26. Further, the plate 34
and combination mount 40 are provided with ports 44 and 46
respectively for communicating hydraulic fluid between the pump and
flexible coupling spaces. Hydraulic fluid may pass between the
flexible coupling and electric motor spaces through the ball
bearing 47.
A removable end plate 48 is transversely mounted within the casing
12 and is spaced from the plate 42. The electric motor 24 has
brushes 49 which are held within brush holders 50 that are mounted
on the removable end plate 48 so as to be located within the space
provided between this plate and the plate 42. Pins 52 combined with
sockets 43 may be utilized for connecting the brushes 49 to the
electric motor 24 so that the brushes can be easily removed with
the plate 48 for inspection and then easily reconnected to the
electric motor after maintenance. The motor armature is splined
where it mates with the flexible coupling so that it may be removed
for commutator maintenance after removal of plate 48.
The casing 12 may include caps 54 and 56 which are mounted at each
end thereof. Male connectors 58 (one shown) may be provided for
carrying d-c electric power to the motor 24. The cap 54 may have a
passageway 60 for receiving a control arm 62 from the compensator
32. The control arm 62 may terminate in a control knob 64 outside
the housing 28 for selectively adjusting the output pressure of the
pump 16 at a desired level above ambient pressure. The outlet tube
22 also extends through this cap 54.
Hydraulic fluid passes through the ball bearing 47 and flows
through the annular space between the motor armature and field. The
plate 42 is shaped like a large washer so that fluid can pass into
the brush area. A hole 65 allows oil to flow from the brush space
into the annular space between the motor and the casing 12.
In the preferred embodiment hydraulic fluid may be returned to the
unit by a pipe 66 through the plate 48. In this way hydraulic fluid
is circulated through the entire unit carrying away foreign
particles which may erode from the brushes and aiding in heat
transfer from the motor. However, it may be desirable in some cases
to use a hydraulic fluid in which d-c electric motor brushes cannot
operate satisfactorily. In this case the hydraulic fluid must be
returned by a pipe (not shown) through the plate 36 and a space 67
may be provided for a shaft seal to prevent the passage of
hydraulic oil into the motor spaces. The motor spaces may be filled
with a fluid which is compatible with the brushes such as hydraulic
fluid MIL-H-5606. This fluid may be compensated to ambient pressure
by means of an external compensator (not shown) which is connected
to the motor spaces by means of a passageway (not shown) through
plate 48. The motor spaces may be filled with fluid through this
passageway. A screw 68 and sealing washer 70 may be provided for
bleeding off air trapped within the case during the filling process
and also for bleeding off gasses generated during operation due to
arcing of the brushes.
In the preferred embodiment filling of the unit with hydraulic
fluid is accomplished through the hydraulic fluid return inlet pipe
66. The screw 68 is used to bleed trapped air from the unit.
In the preferred embodiment a torpedo propulsion motor is utilized
since these motors are generally designed for minimum size and
weight for a given horsepower and also for maximum efficiency. Two
examples of such motors are the propulsion motors for the MK-32
torpedo (5 HP) and the MK-34 torpedo (11.5 HP).
In order to dampen the sound of the operation of the pump 16 the
casing 12 may be provided with an annular recess 74 adjacent the
exterior of the bladder 30 so as to provide a space for containing
seawater therebetween. By such an arrangement noise vibrations of
the pump 16 must travel through the hydraulic oil 14, bladder 30,
seawater within the space 74, and the housing 28 before
transmission to the outside ocean environment. These many
interfaces considerably reduce the noise generated by the pump
16.
The end plates 36 and 48 may be retained within the housing 28 by
snap rings 76 and 78 respectively. The spaces where the hydraulic
pump oil is located may be sealed from the ambient ocean
environment by the various "0" rings shown in FIG. 1.
It is now readily apparent that the present invention provides a
very compact and reliable power unit which will convert d-c battery
power to mechanical energy in the form of pressurized hydraulic
oil. The pressurized hydraulic oil may be utilized for driving
hydraulic thrusters on a deep submersible or for other undersea
purposes.
Obviously many modifications and variations of the present
invention are possible in the light of the above teachings. It is
therefore to be understood that within the scope of the appended
claims the invention may be practiced otherwise than as
specifically described.
* * * * *