U.S. patent number 3,807,912 [Application Number 05/291,968] was granted by the patent office on 1974-04-30 for fluid flow device having high degree of flexibility.
This patent grant is currently assigned to The Keller Corporation. Invention is credited to Leonard J. Keller.
United States Patent |
3,807,912 |
Keller |
April 30, 1974 |
FLUID FLOW DEVICE HAVING HIGH DEGREE OF FLEXIBILITY
Abstract
A fluid flow device useful as a pump having reversible,
infinitely variable flow up to full capacity characterized by a
rotor assembly; a vane assembly movable to effect a desired
direction and degree of eccentricity with respect to the rotor
assembly; an outer housing; and control device for effecting the
desired direction and degree of eccentricity to control the
direction and rate of flow of a fluid such as liquid through the
pump. The device can be employed as a fluid flow motor. Also
disclosed are specific structural embodiments; such as, control
device structure, rotor guide spool structure, relief port
structure for preventing liquid "hammer" and serial interconnection
of a plurality of pumps to enable employing a single power source
while running each pump at its own direction and rate of flow. A
plurality of the devices may be fluidly coupled together in a
pump-motor combination to form an advantageous, infinitely variable
transmission useful for accelerating, sustained movement, or
braking.
Inventors: |
Keller; Leonard J. (Sarasota,
FL) |
Assignee: |
The Keller Corporation
(Sarasota, FL)
|
Family
ID: |
23122638 |
Appl.
No.: |
05/291,968 |
Filed: |
September 25, 1972 |
Current U.S.
Class: |
418/31; 418/241;
418/137 |
Current CPC
Class: |
F01C
1/352 (20130101); F04C 14/223 (20130101) |
Current International
Class: |
F01C
1/352 (20060101); F01C 1/00 (20060101); F03c
003/00 () |
Field of
Search: |
;418/31,137,138,241 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Husar; C. J.
Attorney, Agent or Firm: Wofford, Felsman & Fails
Claims
What is claimed is:
1. A fluid flow device comprising:
a. a rotor assembly including:
i. two circular end discs having a common central axis;
ii. a plurality of guide spools disposed between and connecting the
central portion of said end discs such that said rotor assembly
including the end discs rotates together in unison about said
central axis; each said guide spool having a longitudinally
extending slotted aperture for sealingly receiving a vane; said
longitudinally extending slotted aperture being formed in an
integral body such that said vane can slide freely therewithin as
said guide spools interdigitate said vanes during rotation of said
rotor assembly; and
iii. rotor body elements sealingly interposed between said end
discs at their ends and said guide spools at their sides to define
said rotor body;
b. a vane assembly including:
i. a vane shaft defining a vane axis;
ii. a plurality of angularly related radial vanes that are
connected with said vane shaft and are independently pivotal and
rotatable within a cylindrical chamber of a control device; said
vanes occupying substantially the total radial distance from said
vane shaft to the internal wall of said cylindrical chamber;
respective said vanes being slidably and sealingly disposed within
said longitudinally extending slotted aperture of said guide spools
of said rotor assembly for being interdigitated when said rotor
assembly rotates and said vane assembly is eccentric with respect
thereto; said vane shaft and said vanes sealingly engaging said end
discs of said rotor assembly and slidable therewithin for being
moved to a desired degree of eccentricity;
c. an outer housing having:
i. inlet and outlet ports;
ii. at least one operating shaft aperture and seal means for
receiving a power shaft; and
iii. opposed guide plate receiving means for sealingly and slidably
receiving guide plates of a control device; said outer housing
defining a main chamber therewithin;
d. a control device including:
i. a cylindrical chamber sealingly encompassing said vane assembly
and the outer radial tips of said vanes; said cylindrical chamber
being disposed within said main chamber; said cylindrical chamber
having its end sealingly and slidably engaging said end discs; said
cylindrical chamber having a plurality of inlet and outlet ports on
diametrically opposed sides intermediate guide plates;
ii. guide plates sealingly connected with walls of said cylindrical
chamber and extending outwardly to define separate,
non-communicating inlet and outlet chambers within said main
chamber of said outer housing and about the exterior of said
cylindrical chamber; said guide plates being sealingly and slidably
disposed in said respective guide plate receiving means of said
outer housing; and
iii. positioning means for positioning said cylindrical chamber at
the desired degree of eccentricity with respect to said central
axis of said end plates for effecting the desired rate of flow of
fluid therethrough; and
e. at least one power shaft connected with said rotor assembly.
2. The device of claim 1 wherein said plurality of vanes comprise
6-11, inclusive, vanes.
3. The device of claim 1 wherein the fluid flow device is a
reversible, infinitely variable pump; said vane shaft and said
vanes are slidable within said end discs in at least two directions
with respect to the central axis thereof for reversibility and
infinitely variable flow adjustment within the range of from 0 to
the maximum capacity of the pump in either direction of flow;
wherein said inlet and outlet chambers within said main chamber of
said outer housing are reversible; and said positioning means
positions and cylindrical chamber at both the desired direction and
degree of eccentricity with respect to the central axis of said end
plates for effecting the desired direction and rate of pumping of a
fluid therethrough.
4. The device of claim 3 wherein siid pump is a liquid pump; and at
least one relief port is provided; said relief port communicating
with at least one of said inlet and outlet chambers and the
interior of said cylindrical chamber intermediate the respective
sets of inlet and outlet ports on the high pressure side during
flow for preventing knock by attempting to compress sealed-in
liquid.
5. The device of claim 4 wherein a plurality of relief ports are
provided; at least one respective relief port communicating with
said inlet chamber and at least one respective relief port
communicating with said outlet chamber.
6. The device of claim 5 wherein respective said relief ports are
blocked from simultaneously communicating with both said respective
inlet and outlet chambers during any portion of a cycle where said
relief ports communicate with each other interiorly of said
cylindrical chamber such that said inlet and outlet chambers are
never in communication.
7. The device of claim 3 wherein a plurality of said devices are
connected together by a plurality of intermediate stub shafts and
driven by one power source; each pump being operable with its own
respective direction of flow and its own rate of flow up to the
rate possible at the rate of rotation of the respective shafts and
pumps, and independently of any other pump.
8. The device of claim 1 wherein a plurality of power shafts are
provided, one each being connected in a power delivery relationship
with each end plate so that said shafts and said end plates rotate
in unison.
9. The device of claim 1 wherein the fluid flow device is a
reversible, infinitely variable fluid motor; said motor being
operable to deliver power on its power shaft in response to passage
of a fluid therethrough from a high pressure to a lower pressure;
said vane shaft and said vanes are slidable within said end discs
in at least two directions with respect to the central axis thereof
for reversibility and infinitely variable rotational speed of its
output shaft in coordination with the load being driven by said
output shaft and equivalent to the power available with respect to
the predetermined rate of flow and pressure differential across the
motor within the range up to the maximum capacity at the given
operating condition, wherein said inlet and outlet chambers within
said main chamber of said outer housing are reversible; and said
positioning means positions said cylindrical chamber in both the
desired direction and degree of eccentricity with respect to the
central axis of said end plates for effecting the desired direction
of flow of fluid and the rate of rotation of said shaft connected
with said rotor assembly.
10. The device of claim 9 wherein said fluid motor is an expander
motor and the fluid flowing therethrough is an expansible and
compressible fluid.
11. The device of claim 9 wherein said motor is a liquid motor and
said fluid is an incompressible liquid.
12. A combination of devices in accordance with claim 1 wherein a
first device of claim 1 is a reversible, infinitely variable pump
and a second of said devices of claim 1 is a reversible, infinitely
variable fluid motor; the respective outlet ports of said pump and
said motor are serially connected with the input ports of said
motor and said pump, respectively, by way of fluid-impermeable
conduits capable of containing the pressure of a fluid therein; a
working fluid contained in said pump, said motor, and said
fluid-impermeable conduits so as to deliver power in response to
pumping by said pump and effect rotation of said motor; wherein
said power shaft on said pump is adapted for being connected with a
source of power and said power shaft on said motor is adapted for
being connected with a load; said vane shafts and said vanes of
said pump and said motor being slidable within respective said end
discs in at least two directions with respect to the central axis
thereof for reversibility and infinitely variable adjustments,
respectively, within the range of from 0 to the maximum capacity of
the pump at a particular rotational speed in either direction of
flow, and from 0 to the desired rotational speed of the output of
said motor up to the power available with respect to the
predetermined rate of flow and pressure differential across the
motor as being supplied by said pump; wherein each device has its
said inlet and outlet chambers within said main chamber of said
outer housing reversible; and said positioning means positions said
cylindrical chamber in each said device at both the desired degree
of eccentricity with respect to the central axis of its said end
plates for effecting the desired direction and, respectively, rate
of pumping of a fluid therethrough, and torque and rotational speed
of said motor output shaft.
13. A fluid flow device comprising:
a. a rotor assembly including:
i. two circular end discs having a common central axis; and
ii. body and interdigitating means connecting said end discs such
that said rotor assembly including the end discs rotate together in
unison about said central axis; said body and interdigitating means
having means for sealingly and slidably engaging vanes of a vane
assembly;
b. a vane assembly comprising a plurality of centrally pinned
together vanes that extend radially outwardly through and in
sliding and sealing engagement with said body and interdigitating
means; said vanes being independently pivotal and rotatable within
a cylinder chamber of a control device and forming respective,
separate, variable volume subchambers therewithin; said vanes
sealingly engaging said end discs of said rotor assembly and
slidable therewithin for being moved to a desired degree of
eccentricity;
c. an outer housing having:
i. inlet and outlet ports;
ii. at least one operating shaft aperture and seal means for
receiving a power shaft; and
iii. opposed guide plate receiving means for sealingly and slidably
receiving guide plates of a control device; said outer housing
defining a main chamber therewithin;
d. a control device including:
i. a cylindrical chamber sealingly encompassing said vane assembly
and the outer radial tips of said vanes; said cylindrical chamber
being disposed within said main chamber; said cylindrical chamber
having its ends sealingly and slidably engaging said end discs;
said cylindrical chamber having a plurality of inlet and outlet
ports on diametrically opposed sides intermediate guide plates;
ii. guide plates sealingly connected with said cylindrical chamber
and extending outwardly to define separate, non-communicating inlet
and outlet chambers within said main chamber of said outer housing
and about the exterior of said cylindrical chamber; said guide
plates being sealingly and slidably disposed in said respective
guide plate receiving means of said outer housing; and
iii. positioning means for positioning said cylindrical chamber at
the desired degree of eccentricity with respect to said central
axis of said end plates for effecting the desired rate of flow of
fluid therethrough; and
e. at least one power shaft connected with said rotor assembly.
14. The device of claim 13 wherein the fluid flow device is a
reversible, infinitely variable pump; said vane shaft and said
vanes are slidable within said end discs in at least two directions
with respect to the central axis thereof for reversibility and
infinitely variable flow adjustment within the range of from 0 to
the maximum capacity of the pump in either direction of flow;
wherein said inlet and outlet chambers within said main chamber of
said outer housing are reversible; and said positioning means
positions said cylindrical chamber at both the desired direction
and degree of eccentricity with respect to the central axis of said
end plates for effecting the desired direction and rate of pumping
of a fluid therethrough.
15. The device of claim 13 wherein the fluid flow device is a
reversible, infinitely variable fluid motor; said motor being
operable to deliver power on its power shaft in response to passage
of a fluid therethrough from a high pressure to a lower pressure;
said vanes are slidable within said end discs in at least two
directions with respect to the central axis thereof for
reversibility and infinitely variable rotational speed of its
output shaft in coordination with the load being driven by said
output shaft and equivalent to the power available with respect to
the predetermined rate of flow and pressure differential across the
motor within the range up to the maximum capacity at the given
operating condition; wherein said inlet and outlet chambers within
said main chamber of said outer housing are reversible; and said
positioning means positions said cylindrical member in both the
desired direction and degree of eccentricity with respect to the
central axis of said end plates for effecting the desired direction
of flow of fluid and the rate of rotation of said shaft connected
with said rotor assembly.
16. The device of claim 15 wherein said fluid motor is an expander
motor and the fluid flowing therethrough is an expansible and
compressible fluid.
17. The device of claim 15 wherein said motor is a liquid motor and
said fluid is an incompressible liquid.
18. A combination of devices in accordance with claim 13 wherein a
first device of claim 13 is a reversible, infinitely variable pump
and a second of said devices of claim 13 is a reversible,
infinitely variable fluid motor; the respective outlet ports of
said pump and said motor are serially connected with the input
ports of said motor and said pump, respectively, by way of
fluid-impermeable conduits capable of containing the pressure of a
fluid therein; a working fluid contained in said pump, said motor,
and said fluid-impermeable conduits so as to deliver power in
response to pumping by said pump and effect rotation of said motor;
wherein said power shaft on said pump is adapted for being
connected with a source of power and said power shaft on said motor
is adapted for being connected with a load; said vanes of said pump
and said motor being slidable within respective said end discs in
at least two directions with respect to the central axis thereof
for reversibility and infinitely variable adjustments,
respectively, within the range of from 0 to the maximum capacity of
the pump at a particular rotational speed in either direction of
flow, and from 0 to the desired rotational speed of the output of
said motor up to the power available with respect to the
predetermined rate of flow and pressure differential across the
motor as being supplied by said pump; wherein each device has its
said inlet and outlet chambers within said main chamber of said
outer housing reversible; and said positioning means positions said
cylindrical chamber in each said device at both the desired degree
of eccentricity with respect to the central axis of its said end
plates for effecting the desired direction and, respectively, rate
of pumping of a fluid therethrough, and torque and rotational speed
of said motor output shaft.
Description
BACKGROUND OF THE INVENTION:
1. Field of the Invention:
This invention relates to fluid flow devices, such as fluid motors
or pumps. More particularly, it relates to a liquid pump of the
type commonly referred to as hydraulic pumps.
2. Description of the Prior Art:
A wide variety of fluid flow devices have been known in the prior
art, including rotary fluid motors and a wide variety of positive
displacement rotary pumps. The sliding vane positive displacement
pumps, geared pumps and eccentric rotor, concentric vane positive
displacement pumps are known. For example, as early as 1864 and
1868, U.S. Pat. Nos. 43,744 and 83,186 were granted on rotary steam
engines having implications of serving as pumps.
In the prior art devices, intermediate attempts, such as described
in U.S. Pat. No. 2,129,431, and recent attempts, such as described
in U. S. Pat. No. 3,572,985, employed a semi-cylindrical seal
member slideably engaging each side of planar vanes as they slid
radially inwardly and outwardly along the vanes. Such structure has
the tendency to allow the semi-cylindrical seal members to be
pressed together and grip the planar vanes with an excessive force,
reducing efficiency and prematurely wearing out the vanes. Other
patents, such as U. S. Pat. No. 2,022,207 described employing a
seal having a knife-like edge that engaged planar vanes, attempting
to form a fluid-tight seal as it moved radially inwardly and
outwardly along the vane.
Thus, the prior art devices, either motors or pumps, did not
provide a satisfactory seal that would not grip the vanes with too
much force and effect premature wear. Moreover, the prior art pumps
did not provide a pump in which the rate of flow was infinitely
variable from 0 to full capacity of the pump while the pump was
turning at a given rotational speed in revolutions per minute
(rpm); and, particularly, did not allow full reversibility in
combination with the infinitely variable rate of flow.
Accordingly, it is an object of this invention to provide a fluid
flow device that obviates the disadvantages of the prior art
structures and provides a satisfactory rotor seal that does not
bind the vane.
It is a specific object of this invention to provide a hydraulic
pump having full reversibility in the direction of flow and
infinitely variable rate of flow from 0 to full capacity of the
pump in either direction, even while turning at a predetermined
rotational speed.
These and other specific objects will become apparent from the
descriptive matter hereinafter, particularly when taken in
conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS:
FIG. 1 is an isometric view of a plurality of ganged, or serially
mechanically connected, hydraulic pumps in accordance with one
embodiment of this invention.
FIG. 2 is a side elevational view in partial section of one of the
pumps of the embodiment of FIG. 1.
FIG. 3 is a partial top plan view of the hydraulic pump of FIG. 2
with the top portion of the outer housing and of the cylinder
chamber of the control device removed.
FIG. 4 is a side elevational view of a guide spool intermediate the
end discs and slidably and sealingly engaging a vane in accordance
with one embodiment of this invention.
FIG. 5 is a top view of the guide spool of FIG. 4.
FIG. 6 is a partial cross sectional view taken along the line
VI--VI of FIG. 5.
FIG. 7 is a side elevational view in partial section of a fluid
expander motor in accordance with another embodiment of this
invention.
FIG. 8 is an isometric view, partly schematic, showing a pump and
motor fluidly connected together in a power transmission
apparatus.
FIG. 9 illustrates a vehicular application for a power transmission
similar to that illustrated in FIG. 8.
FIG. 10 is a partial cross sectional view taken along the line X--X
of FIG. 2.
DESCRIPTION OF PREFERRED EMBODIMENTS:
Referring to FIG. 1, a plurality of hydraulic pumps 11, 13 and 15
are serially mechanically connected together by power shafts 17 and
19. A primary input shaft 21 is afforded for connection with a
power source, such as a prime mover or electric motor. Each of the
hydraulic pumps, such as pump 11, has the capability of full
reversal of flow and is infinitely variable in the flow rate
therethrough from 0 to full capacity, independently of the other
pumps and of the rate of rotation at which the shafts and the pumps
are being turned.
As illustrated in FIGS. 2 and 3, also, each hydraulic pump
comprises the main elements or subassemblies of rotor assembly 23;
vane assembly 25; control device 27; and outer housing 29.
The rotor assembly includes two circular end discs 31 and 33; and
body and interdigitating means 35.
The two circular end discs 31 and 33 are larger in radial extent
than the remainder of the rotor assembly 23. The end discs 31 and
33 are rotatably supported by bearing means, such as bearings 37
and 39 disposed peripherally thereof. Also, thrust bearings 41 and
43 are provided intermediate the end discs 31 and 33 and the main
housing 29. Each of the end discs 31 and 33 have means for being
connected with suitable power shafts so as to rotate in unison
therewith and transmit torque therebetween. As illustrated, the end
discs 31 and 33 have centrally disposed splined apertures 45
encompassing their centrally disposed power shafts 17 and 21, that
are aligned to define a central axis. The central axis is also the
central axis for the rotor assembly, where it is concentric, as
illustrated. The power shafts, such as input shaft 21 and output
shaft 17, are similarly splined on their ends so as to conformingly
engage the splined apertures 45 of the end discs 31 and 33. Each of
the end discs 31 and 33 also has a portion of a means for being
connected with the body and the interdigitating means 35 so the
entire rotor assembly rotates in unison, as will be described in
more detail with respect to the assembly of the guide spools 49,
and rotor body elements 51, hereinafter.
The body and the interdigitating means 35 comprise guide spools 49
and rotor body elements 51. As can be seen in FIG. 2, there are a
plurality of guide spools 49, one for each of the vanes. The
plurality of guide spools 49 are disposed between and connect the
central portions of the end discs 31 and 33 such that the rotor
assembly including the end discs rotates together in unison about
the central axis. The guide spools 49, FIGS. 4-6, have a
longitudinally extending slotted aperture 53 for sealingly
receiving a vane 63. Each longitudinally extending slotted aperture
53 is formed in an integral body making up the respective guide
spool 49 such that the respective vane 63 can slide freely
therewithin as the guide spool 49 interdigitates the vane 63 during
rotation of the rotor assembly 23. As illustrated, the guide spools
49 are journalled in the respective end discs 31 and 33. The
respective ends 57 of the guide spools 49 may be journalled in the
suitable bearing means, such as inserts or roller bearings (not
shown) to accommodate the relatively small oscillatory pivotal
motion required for interdigitating the vanes as the rotor assembly
23 rotates.
The motor body elements 51 are sealingly interposed between the end
discs 31 and 33 at their ends and the guide spools 49 at their
sides to define the rotor body. Inherently, when the rotor body
elements are assembled, their central longitudinal axis is
substantially perpendicular to the plane of the end discs 31 and
33. The rotor body elements 51 are fastened to the end discs 31 and
33 by way of suitable machine screws in apertures 52 with dowell
pins 54 on either side to prevent rocking of the rotor body element
51.
The vane assembly 25 comprises a vane shaft 61 and a plurality of
angularly related radial vanes 63. The vane shaft 61 is actually a
floating axle pin that is substantially co-axial with the internal
wall 65 of the control device 27. The vane shaft 61 extends between
the end discs 31 and 33. A plurality of vanes 63 extend radially
outwardly from the vane shaft 61 and are individually pivotal
thereon. Each vane is provided with a curved end face 67 of
substantially the same radius of curvature as the internal walls 65
of the control device 27 which defines the internal surface of the
vane assembly cavity 69. The curved end face 67 of each vane 63,
whether in the form of a seal, per se, or the bare end, is in
substantial sliding engagement with the wall 65 such that it forms
a satisfactory seal for confining the fluid in the respective
subchamber on either side of the vane.
Any appropriate number of vanes may be employed. Generally, there
are employed as many as can be mechanically achieved without
sacrificing too much cross sectional area of the rotor body or
making the diameter of the guide spools too small to allow them to
function properly. Ordinarily, 6-11 vanes will be employed,
depending upon the size, use or application, capacity of the
machine, operating pressure desired and speed the machine will run,
as well as other variables well known to the engineer. As
illustrated, 8 vanes are employed in FIG. 2. The vanes are
pin-connected to the common vane shaft 61 at the center of the
assembly. The specific structure for interconnection of the vanes
and the respective shaft, or axle pin, are specifically illustrated
in my co-pending application Ser. No. 227,384 and reference may be
had thereto for details. As described therein, the shaft 61 fits
through collars on the radially interior vane ends. The collars are
symmetrical about a plane through the center of the vane and are
perpendicular to both the respective vane 63 and the vane shaft 61.
One vane has a single center collar twice the width of the twin
collars on the remaining vanes so that all are symmetrical about
the plane above-mentioned. Consequently, both pressure forces and
acceleration-deceleration forces on the collars are evenly
distributed.
The vanes 63 penetrate through the slotted apertures 53 in the
guide spools 49, as previously described with respect to FIGS. 4-6.
The slotted apertures 53 sealingly engage and slide radially
inwardly and outwardly along the vanes 63 as the vanes are
differentially interdigitated by rotation of the rotor assembly
23.
The vane assembly 25 is held in its desired position by the
cylindrical inner wall 65 of the control device 27 defining the
vane assembly cavity 69 inside which the vanes rotate as they are
differentially interdigitated by the rotor assembly 23. The
interdigitating of the vanes, coupled with simultaneous rotation of
the vane assembly 25 within the vane assembly cavity 69 thereby
effects simultaneous increases; and, alternatively, simultaneous
decreases; in two of the three subchamber dimensions upon rotation
when eccentrically positioned with respect to the center of the
rotor assembly 23. When the control device 27 moves the vane
assembly 25 such that its center is the same as the center of the
rotor assembly 23, however, there is no differential
interdigitating. Therefore, there is no subchamber dimension
changes even though there is rotation. Consequently, no pumping
takes place even though the machine rotor assembly and the vane
assembly may be rotating at the usual speed.
The outer housing 29 contains the fluids and directs their flow in
response to pressure differential induced by the rotating vane
assembly 25. The outer housing 29 defines a main chamber
therewithin and retains the respective components in their proper
relationship. As illustrated in FIG. 10, the outer housing 29
slidably and sealingly engages the end discs 31 and 33 to contain
the fluid therewithin. The outer housing 29 has inlet and outlet
ports 73 and 75, FIG. 2; at least one power shaft aperture 77 and
seal means 79; and opposed guide plate receiving means 81 and 83.
The inlet and outlet port 73 and 75 have respective manifold means
85 for connection with suitable conduit in a flow system, as by
flanges and stud bolts. Appropriate side covers 113, FIGS. 1, 3 and
10, may be affixed to a central member 115 by any conventional
means such as machine screws (not shown) to effect the outer
housing 29. From the descriptive matter, it can be seen that the
respective inlet and outlet ports 73 and 75 may be reversed
depending upon the direction of the vane shaft 61 with respect to
the central axis of the rotor assembly 23. As illustrated, the
housing 29 has a pair of oppositely disposed operating shaft
apertures for interconnecting respective shafts 17 and 21
intermediate the end discs 31 and 33. The seal means 79 may
comprise any suitable seal for sealing intermediate the respective
shafts 17 and 21 and the encompassing housing 29. Suitable shaft
bearings 87, such as roller bearings, may be employed about the
shaft interiorly of the seal 79, if desired.
The opposed guide plate receiving means 81 and 83 comprise slots
having rectangular cross section for sealingly and slidably
receiving the guide plates 89 and 91 of the control device 27.
The control device 27 includes a cylindrical chamber serving as the
vane assembly cavity 69 and defined by the generally cylindrical
member 93; guide plates 89 and 91 referred to hereinbefore; and
positioning means 95. The cylindrical chamber is a right circular
cylinder defined by the cylindrical member 93 inside and sealingly
engaging the two opposed and parallel end discs 31 and 33.
Expressed otherwise, the cylindrical member 93 is in essentially
sliding sealing contact with the end discs 31 and 33. The central
axis of the cylindrical chamber is normal to the plane of the
respective end discs 31 and 33. The cylindrical member 93 has a
plurality of inlet and outlet ports 97 and 99 in diametrically
opposite sides intermediate the guide plates 89 and 91. Expressed
otherwise, the inlet and outlet ports comprise a plurality of
apertures arranged to divide the two sides of the pump into an
inlet side and an outlet side; although the sides may be
interchanged one for the other by moving the control device across
to position the vane shaft 61 on the other side of the central axis
of the rotor assembly 23.
The guide plates 89 and 91 are sealingly connected with the
cylindrical chamber via the cylindrical member 93 and extend
outwardly to define separate, non-communicating, and reversible
inlet and outlet chambers 101 and 103 within the main chamber of
the outer housing 29. The inlet and outlet chambers 101 and 103 are
disposed about the exterior of the cylindrical chamber, or vane
assembly cavity 69, and are reversible, as indicated hereinbefore.
Similarly, as indicated hereinbefore, the guide plates 89 and 91
are sealingly and slidably disposed in the respective guide plate
receiving means 81 and 83 of the outer housing 29.
The positioning means 95 may comprise any means able to deliver the
force required to position and retain in position the control
device 27. As illustrated, the positioning means comprises rack
105, and a pinion 107 mounted on a power driven shaft 109. The
power driven shaft 109 may be powered manually as by a lockable
crank, but preferably will be driven by a suitable motor and brake.
A reinforcing roller 111 is employed to prevent slippage between
the gear teeth on the rack and pinion 105 and 107 and ensure
delivery of the requisite force to move the control device 17. As
implied hereinbefore, the positioning means 95 is employed for
moving the cylindrical member 93 with its internal cylindrical
chamber, or vane assembly cavity 69, to the desired degree of
eccentricity in the desired direction with respect to the central
axis of the end plates, or the rotor assembly 23, for effecting the
desired direction and rate of flow of fluid through the pump.
At least one relief port 117 is provided to prevent liquid
"hammer," caused by inadvertently attempting to compress sealed-in
liquid intermediate the rotor assembly 23, respective vanes and the
inner wall 65 of the cylindrical member 93. The relief port
communicates with at least one of the inlet and outlet chambers,
such as inlet chamber 101, and the interior of the cylindrical
chamber defining the vane assembly cavity 69. The internal
communication, or end of the relief port 117 is located
intermediate the respective sets of inlet and outlet ports 97 and
99 during flow for preventing the liquid hammer. As illustrated, a
plurality of relief ports 117 and 119 are provided. At least one of
the relief ports communicates with the inlet chamber 101 and at
least one of the relief ports communicates with the outlet chamber
103. To prevent communication between the respective inlet and
outlet chambers 101 and 103 which should never be in communication,
it is imperative that the relief ports be blocked from
simultaneously communicating with both the respective inlet and
outlet chambers and the same subchamber defined by the respective
vanes interiorly of the vane assembly cavity 69. Expressed
otherwise, the vane 63a, FIG. 2, must block off the inlet to the
relief port 119 before the vane 63b opens the inlet to relief port
117. Otherwise, there would be flow from the high pressure, or
outlet, chamber 103 to the inlet chamber 101. As can be seen by
considering the relief ports on the left hand side of FIG. 2, the
relief ports may communicate with each other interiorly of the vane
assembly cavity while the respective vanes are spread apart without
adverse consequences, since the other end of the respective relief
ports are sealed by the guide plate receiving means 83 and prevents
communication with the inlet and outlet chambers 101 and 103.
In operation, one or more hydraulic pumps 11, are connected
together, as by power shafts 17 and 19. The respective elements of
the pump will have been assembled as indicated hereinbefore. The
positioning means 95 is operated to obtain the desired degree of
eccentricity of the vane assembly 25 in the cylindrical member 93,
with respect to the central axis of the rotor assembly 23. Rotation
is effected by means of interconnection of the one or more power
shafts with a power source, such as an electric motor or prime
mover. If the rate of flow effected at the achieved rpm is too low
or too high, it can be adjusted by moving the positioning means to
move the control device 27 and bring the vane axis 61 nearer to or
farther away from the central axis of the rotor assembly 23;
thereby, respectively, decreasing or increasing the flow through
the hydraulic pump 11. As can be seen, the rotor assembly 23
rotates and effects rotation of the vanes 63 of the vane assembly
25, simultaneously interdigitating the vanes 63 and effecting
pumping of the fluid through the pump. Expressed otherwise, the
fluid will be picked up through inlet ports 97 and conveyed to the
outlet ports 99. The fluid will be discharged through the outlet
ports 99, since the volume of the respective subchambers defined by
the vanes decreases upon further rotation in a clockwise direction,
as viewed in FIG. 2.
If it is desired to cease pumping fluid, the control device 27 is
moved to position the vane shaft 61 at the central axis of the
rotor assembly. The pump may continue to rotate freely but will
effect no pumping action since the subchambers defined intermediate
the vanes 63 and the end discs 31 and 33 do not change size with
such concentric arrangement. The pump 11 displaces a quantity of
fluid per revolution that is proportional to the distance of the
vane shaft 61 from the central axis of the rotor device. Flow is
therefore infinitely variable between 0 and the maximum capacity of
the pump at the given rotating speed, as indicated hereinbefore.
Thus, two primary variables can be employed in controlling
accurately the rate of flow; the variables being the rotating speed
of the pump and the position of the control device 27.
Moreover, by moving the vane shaft 61 on the other side of the
center of the rotor assembly, the flow is reversed for the same
direction of rotation; and, similarly, is infinitely variable in
the range from 0 to the maximum capacity of the pump. This
flexibility has been long sought, but not achievable, heretofore,
with positive displacement pumps; except for the axial piston type
wobble plate units, which are plagued with various problems and are
limited in capacity.
Suitable splined sub shafts may be employed to serially connect any
number and size of pumps as desired so that multiple units may be
stacked one on the other and driven by one input shaft. The
succeeding interconnecting shafts allow any accumulation of pumps
for a given multi-component system, yet direction and rate of flow
from the respective pumps can be controlled by positioning the
control device 27, with a great degree of independence from the
speed at which the pump may be rotating.
MOTOR APPLICATIONS:
The previously described device can be employed, also, as a fixed
displacement and a variable displacement expander motor.
As illustrated in FIG. 7, the expander motor 123 comprises the same
elements of: the motor assembly 23, the vane assembly 25, the
control device 27 and the outer housing 29. The rotor assembly 23
and the vane assembly 25 are constructed similarly as described
hereinbefore.
The outer housing 29 is also constructed similarly as described
hereinbefore, although the respective inlet and outlet ports 73 and
75 may be located more closely adjacent each other for greatest
efficiency. The control device 27 has its usual guides 89 and 91
but includes a control ring 125. The positioning means 95 comprises
a cam means 133 having a camming surface 135 for moving the
cylindrical member 93 within the main chamber of the outer housing
29 for controlling the rate of flow, as described hereinbefore. Any
suitable means may be employed for keeping the shaft 137 contiguous
the camming surface 135. As illustrated, a strong spring 139 is
employed, the spring pushing against washer member 141 that is
connected with the shaft 137.
In operation, the fluid under elevated pressure flows through inlet
port 73 and through the inlet apertures 143 of the control ring 125
into the respective subchambers defined by the vanes of the vane
assembly 23. As the fluid expands, work is done, similarly as
described in my previously filed and copending application Ser. No.
227,393, entitled "Rotor Vane Motor Device," filed Feb. 18, 1972.
The amount of work done in expansion of the fluid may be controlled
by the control device 27. In the illustrated position, the motor
123 will have its greatest expansion ratio and efficiency. Movement
of the control ring 125 to the right, as viewed in FIG. 7, will
give a greater mass rate of flow at the expense of lowering the
expansion ratio and the efficiency of the motor 123.
On the other hand, the motor 123 may be operated as a motor by
flowing an incompressible fluid therethrough. The motor 123 is
operated as incompressible fluid motor by supplying the
incompressible fluid, such as hydraulic fluid or oil, at some
pressure at the inlet port; flowing the fluid through the motor
123; and discharging the fluid at a lower pressure at the outlet
port. Either of the ports 73 and 75 may be employed as the inlet
port, with the other opening serving as the outlet port. Where an
incompressible fluid is employed and there is a full reversibility
option, it will ordinarily be desirable to employ a plurality of
the apertures 143, similarly as illustrated with respect to
apertures 145. For convenience, the motor 123 is referred to as a
"hydraulic motor" when operated on an incompressible fluid. If
desired when the motor 123 is operated on an incompressible fluid,
relief ports, such as the relief ports 117 and 119, FIG. 2, may be
employed if the apertures 143 and 145 are so spaced that there is a
likelihood of having liquid hammer. The same precautions with
respect to location and venting of the relief ports in pump 11
described hereinbefore are applicable to the hydraulic motor
123.
As described hereinbefore, the hydraulic motor 123 may cease to
develop torque as the control device 27 is moved such that the
center of the vane shaft 61 is aligned with the center of the rotor
assembly 23. As the control device 27 is moved into an eccentric
position, however, the hydraulic motor 123 rotates in one direction
or the other, depending upon which direction in which the control
device is moved and the flow of fluids through the hydraulic motor
123. The shaft rotation is, consequently, reversible without
changing direction of fluid flow into and out of the main housing
by way of the respective ports 73 and 75. The hydraulic motor 123
will have an output torque on its output shaft, such as shaft 153,
FIGS. 7, 8 and 9, that is proportional to the amount of
eccentricity and to the difference between the inlet pressure and
the outlet pressure. Thus, the output torque is completely variable
from 0 to a maximum for any set of inlet and outlet pressure
conditions and the flow of fluid therethrough.
The shaft rotating speed at a given rate of flow of fluid through
the hydraulic motor 123 is inversely proportional to the
displacement per revolution of the motor 123. The displacement per
revolution of the motor 123 is variable and is controlled by the
amount of eccentricity. The shaft speed of rotation in actual
operation will depend upon the output torque of the motor 123 and
the resistance of the load to that torque. Under low levels of
torque resistance, or load, the shaft speed attainable becomes very
high as the volume capacity per revolution approaches 0. This
allows high speed operation at low load. On the other hand, at a
fully eccentric position, the volume capacity per revolution
approaches its maximum, the greatest torque is developed, and the
shaft speed is at its lowest. The hydraulic motor 123 has a flow
capacity and power delivery capability that is from 10 to 20 times
as great as the power and capacity of the best conventionally
available fluid motors, such as the axial piston type motors, now
in common use.
The high shaft speed capability of the hydraulic motor 123 gives it
a broad range of speed variability and allows a high degree of
flexibility in design applications. For example, the hydraulic
motor 123 could be used to accelerate the wheels of an aircraft to
runway speed prior to touchdown when landing for greater safety and
reduced tire wear. The hydraulic motor 123 could also provide wheel
driving capability independent of the propulsion motors of the
aircraft, having high moving torque at low taxi speeds and
relatively constant horsepower with diminishing torque as speed
increases up to take-off speed. On the other hand, the hydraulic
motor 123 could be employed as a pump against which loading is
applied, as by a pump-motor combination, to assist in braking
aircraft wheels during landing and deceleration.
PUMP-MOTOR COMBINATION;
The hydraulic pump 11 and the hydraulic motor 123 can be combined
into a power transmission package that allows full reversibility of
pump and motor functions to afford unprecedented flexibility, yet
provide unique advantages over conventional and similar units.
FIG. 8 illustrates a typical such interconnection in which the pump
11 is serially coupled with the motor 123 to provide a complete
variable-speed ratio power transmission. The hydraulic pump, or
pump unit, 11 is coupled to a prime mover, or power source, by way
of its shaft 21. The hydraulic pump 11 is fluidly connected with
the motor 123 by way of high pressure conduit 149 and low pressure,
or return, conduit 151 to form a closed cycle system. Specifically,
the outlet port on the pump 11 is connected to the fluid inlet port
of the motor 123. The motor unit 123 has an output shaft 153 that
is connected with the respective end discs such as 31 and 33, FIGS.
2 and 3. The output shaft 153, FIGS. 7-9, is then coupled to the
load; such as the wheel 155 in FIG. 9. The output port of the motor
123 is fluidly coupled with the inlet port of the pump 11 via the
low pressure conduit 151 for a return of the incompressible fluid,
such as hydraulic fluid. The fluidly coupled pump 11 and motor 123
provides an infinitely variable ratio, within broad limits, between
the input shaft speed and the output shaft speed, allows full
reversibility of functions for either supplying power for
acceleration or braking for deceleration, at the choice of the
operator. For instance, an automobile could run down grade at a
high rate of speed, but with its engine idling and have the
hydraulic pump 11 still connected directly to the drive wheels.
Yet, the same vehicle could climb a steep grade with its engine
running at a maximum speed and the vehicle creeping along at a few
miles per hour. All ratios between these limits would be available,
as well as the ability to come to a complte stop without the need
for disengaging a clutch; all simply by properly positioning the
center of the vane assembly 25 with respect to the center of
rotation of the rotor assembly 23. Moreover, the illustrated
combination of pump 11 and motor 123 provides the ability to
reverse without shifting gears in the transmission and provides
almost unlimited ability to brake the vehicle with good control,
using the power transmission to do so.
It is immaterial in the illustrated serial fluid connection between
the pump 11 and the motor 123 whether the pump and motor are
physically joined together or even in a common housing; or removed
from each other, aside from the hydraulic horsepower lost in
flowing the fluid through the respective high pressure and low
pressure conduits 149 and 151. FIG. 9 illustrates a specific
application in which the pump 11 pumps the hydraulic fluid through
a hydraulic motor 123 that is directly connected with a wheel 151,
affording a fluid drive on a vehicle, either on highway vehicles,
such as a car or truck, or off highway vehicles, such as earth
movers. The pump 11 and motor 123 are connected by suitable high
pressure conduit 149 and low pressure conduit 151 that may be
piping and flexible tubing means that are conventionally employed
in high pressure fluid flow. The working fluid is recirculated, as
with a conventional pump-motor combination.
The pump 11 and the motor 123 power transmission offers further
versatility and advantages as follows. A mobile vehicle could be
operated through the full range of vehicle speeds and power
requirements while operating the engine at either a constant, or
relatively constant rotational speed. The engine could be
programmed to operate at the optimum efficiency at all times, or it
could be programmed to operate at the minimum pollution level at
all times, yet effect the desired power transmission. A small
hydraulic motor can be employed on each wheel and a relatively
low-emission automobile can be provided at a cost competitive with
conventional equipment and with virtually complete design
flexibility. For example, a Rankine cycle, turbine-driven
automobile becomes theoretically feasible with such a transmission
available. Moreover, a diesel engine with low pollution emission
accoutrements can meet the 1975 emission standards required when
the illustrated power transmission is employed. Also, even the low
efficiency gas turbine engines can be operated at high rpm and
become theoretically feasible when the combination pump 11 and
motor 123 are employed as the transmission.
One significant aspect of the transmission comprising pump 11 and
motor 123 is that an energy storing flywheel can store sufficient
energy at relatively high rpm to maintain engine speed during power
demand surges so that overfueling as a means of providing
acceleration can be avoided to further reduce pollution emission
levels from the engine.
GENERAL:
Although splined shafts and apertures have been disclosed as the
means of interconnecting the operating shafts 17 and 21 with the
end discs 31 and 33, any other satisfactory means of connecting the
power shaft with the end discs can be employed.
The guide spools 49 may be connected with the end discs 31 and 33
by being fixed between shoulders of the end discs by cap screws
penetrating through apertures in the end discs 31 and 33, similarly
as described with regard to shaft 73 affixed to circular rotating
plates in my co-pending patent application Ser. No. 227,384,
entitled "Rotary Vane Device," filed Feb. 18, 1972. Allowance must
be made, however, for oscillatory pivotal motion for
interdigitating the vanes. Moreover, any other interconnection
means may be employed if it effects the results described
hereinbefore.
Any satisfactory positioning means 95 may be employed if it will
effect the positioning of the control device 27 against the forces
involved. For example, hydraulic rams may be employed to effect the
requisite positioning. In the hydraulic pump application wherein
high pressure hydraulic fluid is delivered through the discharge
aperture; the camming means, as described with respect to the motor
123, may be preferable. When such a camming means is employed, it
may be desirable that the shaft 137, or its equivalent, in the
hydraulic pump employ positive engaging means to engage a camming
recess such that it is forced in both directions to enable full
reversibility and full pressure in either direction of flow;
instead of employing a strong spring 139 to keep the shaft 137 in
engagement with the camming surface 135.
From the foregoing, it can be seen that this invention provides a
structure that can be employed either as an expansion motor for
flow of an expansible fluid therethrough to deliver power, or as a
fully reversible, infinitely variable hydraulic pump. It is
particularly in the latter application that this invention has
usefulness because of its exceptionally high degree of flexibility.
The hydraulic horsepower that is capable of being delivered by a
given size unit is amazingly higher than any apparatus of the prior
art. For example, we have found a unit employing a 2 inch rotor
assembly capable of delivering 46 hydraulic horsepower at a
discharge pressure of 3,200 pounds per square inch (psi) and a flow
rate of 24 gallons per minute at a speed of only 300 rpm as
contrasted with conventional units turning 1,800 rpm. The hydraulic
pump of this invention can be employed in a space requirement of
only 220 cubic inches compared with a space requirement of 1,650
cubic inches with the best conventional hydraulic pump currently
available and delivering the same hydraulic horsepower and flow
capability. The advantages of the motor and the combination
pump-motor transmission have been specifically delineated
hereinbefore.
Thus, this invention provides the objects delineated
hereinbefore.
Although this invention has been described with a certain degree of
particularity, it is understood that the present disclosure has
been made only by way of example and that numerous changes in the
details of construction and the combination and arrangement of
parts may be resorted to without departing from the spirit and the
scope of this invention.
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