Note: Descriptions are shown in the official language in which they were submitted.
CA 02487334 2004-11-24
ROTARY MACHINE
This invention relates to mechanical engineering and may be used in high-
pressure low
pulsation reversible machines, able to operate both as a motor and a pump.
Gaseous and
liquid working fluias are applicable.
In known adjustable rotary machine (UK 2207953), the rotor is mounted w,thin
the
housing containing inlet and outlet openings. The rotor has the slots
containing radially
sliding valves. The pump comprises of a mechanism for positioning the valves
in the rotor
slots, a working chamber, and a regulating member movable in radial direction.
Taken as the closest prior-art a high-pressure low pulsations reversible
adjustable pump
(RU 2123602) comprises housing with inlet and outlet openings, and a rotor
mounted
inside the housing. The rotor has the slots for the valves which are able to
reciprocate
along the rotor rotation axis. (Further, instead of the term "valve" the more
common one
"displacer" will be used). The pump comprises mechanism mounted in the housing
providing for axial positioning of the displacers in the rotor slots, a
working chamber, and
a partition which, together with the rotor, separates the suction and pumping
spaces, thus
preventing back flow of the working fluid between them. This partition is
actually the one
of the insulating members preventing back flow of the working fluid between
the pump
*cavities, and a special case of one of the partitions, since any pump of this
design has at
least two partitions.
In this pump the working chamber is bounded in axial direction on one side by
the surface
of the rotor flank which has a sliding contact with the partition and is
called the first flank
of the rotor and on the other side by the regulating member which actually is
a movable
insulating member namely the second partition mounted opposite to the first
flank of the
rotor and moving axially.
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Rotor pumps of this desigtt always have two distittguishable groups of
atembers, which
simultaneously rotate relative to one another with equal values of the angular
velocity and
in opposite directions mround their common axis. Usualty they distinguish one
by one basic
member in each group aed these two members rotating relatively to one another
cause
rotation of the rest of the pump elements. One of these basic members is
usually called the
rotor and the other one relative to which the 'rotation is viewed is called
the stator (or also
often it is called the housing).
The tcrms "rotor member" and "stator member" (hereittafter `5rotor" and
"stator") a[e
relative and depead only or- which member is viewed as rotating relative to
the other one.
It should be noted that all rotarions are viewed (unless something elte is
mentioned)
relative to the common axis of rotatiott and the axial direction means that
one is parallel to
.this commtm axis of rotation.
When the rotor starts to rotate relative to the stator, the assembly of the
pump members
loinematicallytied to the rotor starts rt-tating as well. The combination of
these mernbers
-15 and the rotor itself wiil hereinafter be eallod the rotor tmit. The test
of the pump membets
which do not rotate together with the rotor reladve to the stator and the
stator itself will
hereir>afur be called the stator unit. It's always possible to distinguish the
asscmbly of
parts forming the pump working chamber in the rotor unit and the stator unit.
'lU working
. chamber comprises of a suction space and a pwnpittg space, and the metnbers
which are
3o the working parts of the pump that directly do the work of delivering the
working fluid
from the suction space to the pumping space can also be distingaished in the
rotor unit and
the stator unit. The suction and pumping spaces are the working spaees of a
ptmnp (which
are connected correspondingly to the inlet and outlet ports). In the
aforementioned pumps
when the rotor unit and the staw unit do one revobttion of thair tntxwl
rotation the
25 working parts of these units do rotational movements as weil, together with
the above
- -= _ ..^
CA 02487334 2004-11-24
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mentioned units, besides the working parts of one of these units also do the
cyclic
movements along their common axis of rotation per every revolution of this
unit and
together with the working parts of the second unit (other unit) which do not
do such cyclic
movements.
The pump unit in which the members that are the working parts do also the
cyclic
movements along the common axis of rotation per every revolution of the rotor
will
hereinafter be called the rotor unit and accordingly, the basic member of it
will be called
the rotor. The rest of the unit will hereinafter be called the stator unit and
accordingly the
basic member of it will be called the stator.
It should be noted that rotation of the rotor will be always viewed relative
to the stator, no
matter what device the stator is mounted on to provide rotation of the rotor
relative to the
stator.
In many practical cases of the present invention usage, the pump member called
the stator
may be mounted on a rotating shaft of a certain device, whereas the pump
member called
the rotor may be mounted on a frame or another rotating shaft of the same
device.
Hereinafter all rotations of the rotor will be viewed relative to the stator
in accordance with
the above mentioned meanings of these terms. The working parts which rotate
with the
rotor and directly do the work of delivering the working fluid to the pumping
space of the
pump are usually called displacers (hereinafter we will use this term), and
the members of
the stator unit which together with the members of the rotor unit which
separate the suction
space from the pumping space are called partitions (hereinafter we will use
this term). In
adjustable types of pumps one of the partitions is usually mounted so that it
can move
relative to the rotor and is called the regulating member. The suction space
is connected to
the inlet port and the pumping space is connected to the outlet port. The
pumps with one
cycle of the displacers' movement per one revolution of the rotor always have
at least two
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partitions which separate the suction space from the pumping space. Two cycle
pumps
have twice the number of partitions, three cycle pumps have three times the
number of
partitions, etc.
The difference between the distances from the rotor to the flanks of the
partitions faced to
the rotor determines the delivery per one rotor revolution for this type of
pump (in other
words the axial distance between the flanks of the partitions faced to the
rotor de.ermines
the delivery per one rotor revolution for these pumps).
When chosen as the prior-art rotary machine operates as a pump it is not
possible to
reverse the direction of working fluid delivery without reversing the rotor
rotation
direction. When it operates as a hydraulic motor it is also not allowing
reversing the rotor
rotation direction without reversing the direction of working fluid delivery.
The object of the present invention is to widen the range of functionality for
such rotary
1s machines and to improve their operating parameters.
This problem has been solved by the design of the rotary machine which
comprises the
combination of the members of a stator unit and a rotor unit, namely it has a
stator, a rotor
with slots in which the displacers capable of moving along the axis of the
rotor rotation are
located, a mechanism for setting the axial mutual disposition of the
displacers, a working
chamber bounded in axial direction by the first flank of the rotor and
including a suction
space and a pumping space, a partition mounted on the stator opposite the
first flank of the
rotor and a regulating member mounted on the stator opposite the first flank
of the rotor (in
the same place) movable axially; accordingly to the present invention the
rotary machine
has an additional working chamber bounded axially by the second flank of the
rotor and
CA 02487334 2008-02-14
comprising of its own suction space and pumping space (the flanks of the
displacers
extend to these spaces), a partition and a regulating member mounted both on
the stator
opposite the second fiank of the rotor, the regulating member is mounted so
that it can
move axially, besides the regulating member is positioned so that its tlank
perpendicular to
5 the axis of the rotor rotation is located opposite to the perpendicular to
the axis of the rotor
rotation flank of the partition, which is mounted on the stator opposite the
first Elank of the
rotor and the partition nwunted opposite the second flank of the rotor is
mounted so that its
flank perpendicular to the rotor rotation axis is located opposite the
perpendicular to the
rotor rotation axis flaok of the regulating member which is mounted on the
stator opposite
to the first flartk of the rotor and the regulating members are tied to one
another via a rigid
lcirtematie joint so that the movement of one regutating member causes the
othcr regulating
member to move, moreover the working spaces of both working chambers located
axially
opposite one another are connected between themselves by the channel and a
mechanism
for setting the axial mutual position of the displacers is designed so that it
insures sliding
t s contact of each regalatiug member with at least one displacer.
lntroducing the above mentioned features to the rotary machine makes it
po,:sible to
reverse the direction of working fluid delivery without reversing the rotor
rotation direction
and without using any special switch apparatuses when the machine operates as
a pump.
When it operates as a hydraulic motor it is possible to reverse the rotor
rotation direction
20 without reversing the direation of working fluid delivery.
Moreover the effort required to apply the regulating members to control the
rotor machine
does not depend any more on the working pressure in the system and the
variations of the
pressure in the system caused by irregular load of the pump do not transmit
through the
working fluid to the mechanism of the displacers axial positioning and to the
delivery
25 regulating unit. This allows to depwt from a hydraulic actuator in the
regulating unit and to
CA 02487334 2004-11-24
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decrease the control time of the rotary machine. Such mutual positioning of
the regulating
members and the partitions allows for this type of the rotary machines to
reverse the
direction of working fluid delivery by using just one set of displacers, one
mecha.iism for
setting their axial mutual position and to have the rotor completely balanced
from the
working fluid pressure forces acting on the rotor flanks.
Besides that in the particular embodiment of a rotary machine in order to
unload the rotor
from radial pressure forces of the working fluid, and to diminish radial
vibrations of the
rotor and the noise caused by them as well as to diminish the fluid friction
on the walls
bounding the working chamber radially both working chambers may be bounded
radially
by the surfaces of the annular grooves provided in the opposite flanks of the
rotor so that
they pass through the channels in the rotor, wherein the displacers are
located and the said
channels form recesses in the inner surfaces of the annular grooves by
intersecting them.
In other words the annular grooves are disposed at the rotor flanks so that
they pass
through the rotor bores wherein the displacers are located and the radial
width of the
annular cylindrical grooves is less than the width of the displacers. The
bottom of the first
annular groove is actually the first flank of the rotor and the bottom of the
second groove is
the second flank of the rotor.
The combination of all the above mentioned features introduced into a rotor
machine
widens its functionality, namely: it allows to reverse the direction of
working fluid delivery
with invariable direction of the rotor rotation when this rotary machine
operates as a pump;
to reverse the direction of the rotor rotation under fixed direction of the
working fluid
delivery when this rotary machine operates as a hydraulic motor; to increase
the control
speed, to get a constant regulating effort independently of the working
pressure in the
system, to simplify the design, and to increase essentially the resistance
with respect to
abrupt pressure jumps in the system which the machine is connected to.
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In common with the other types of rotary machines this machine may have a
multi-
chamber design with several working cycles of the displacers per one rotor
revolution.
The essence of the present invention is clarified by the drawings which
represent:
F1G.1 is a rotary machine with three quarters of the housing and the rotor
omitted.
FIG.2 is a section of the rotary machine taken through the plane of the
channels of the
housing.
FIG.3 is a section of the rotary machine; shaft-side view.
FIG.4 is a section of the rotary machine; view in the direction of the inlet
and outlet ports.
FIG.5 is a rotor with displacers.
FIG.6 is an unfolded side view from the center of the working chamber.
The rotary machine of the present invention embodiment (FIG.1) comprises of
housing
(stator) 1 with end closures 2 and 3. Rotor 5 is mounted on shaft 4 within
housing 1. Bores
6 are made through rotor 5 wherein axially movable displacers 7 are located.
The flank of rotor 5 which is opposite end closure 2 and called the first
flank of rotor 5 has
annular groove 8 passed through bores 6. Also the flank of rotor 5 opposite
end closure 3
has a similar annular groove 9 which is made so that it passes through bores 6
as well. The
annular grooves 8 and 9 are made so that bores 6 form recesses 10 in their
inner cylindrical
surfaces. The rotor machine comprises partition 11 mounted on end closure 2
opposite the
first flank of rotor 5 and axially movable regulating member 12 mounted on the
same end
closure 2 opposite the same flank of rotor 5. The flank of partition 11 is in
sliding contact
with the bottom of annular groove 8.
This annular groove 8 together with end closure 2 bounds the first working
charnber.
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a
Partition 1 l and regulating member 12 divide this working chamber into
suction space 13
and pumping space 14 (F1G.6). Suction spacel3 is connected to inlet port 15
and pumping
space 14 is oonnecttd comespondingly to outlet port 16. Tte said rotary
machine has
panition 17 (FIG.2) mounted on end closure 3 opposite the second flank of
iotor 5 aad
axially movable regulating member 18 mounted on the same ead closuwe 3
opposite the
same flank of rotor S. The flank of partition 17 is in sliding eontsct with
the bottom of
annuiar groove 9. This annular groove 9 together with end closure 3 bounds the
aAditional
working chamber. Partition 17 and regulating member 18 divide the additional
working
chamber into suction spaee 19 and pumping space 20 (FIG.2). Partition 17 is
mountiod so
that its tlanic faeing the second flank of rotor 5 is locased opposite the
flank of regulating
member 12 tnoanted opposite the first flank of rotor 5. And regulating member
18 is
mounted so that its flank facing the second flank of rotor 5 is located
opposite the flank of
partition 11 which is opposite the fust tlazilc of rotor S. Suction space 19
(FIG.2) of the
additional working chamber is eonnocted vis- chenne121 to pumping spaee 14
(FIG.6) of
the first working chamber and pumping space 20 (Fia.2) is connected via
charu.el 22 to
suction spaoe 13 (FIG.6). These slots pass through housing I but in the
general
embodiment of the present invention they can be made in the rotor and in the
displacers but
it is importutt tlmt thc slota corotect the opposite ohambers of the rotary
machine.
The rotary machine comprises the mechanism positioning the displacars 7
axially which is
made so, that it encures slding contact between at least one of the
displacers and each of
regulating members 12 and 3 B. The mechartism for positioning the displacers
axially is
made by a hollow cylinder surrounding rotor 5 and mounted so that it can move
axally.
On the inner surface of this bollow cylinder closed curved groove 24 is made
so that its
curvature defines the axial mutual position of displacers 7. Besides that each
displacer 7 is
supplied with foliower 25. These followers 25 enter closed curved groove 24.
Closed
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curved groove 24 is made so that at least one of displacers 7 disposed
opposite the flank of
regulating member 12 is in contact with the flank of the regulating member 12
and at least
one of displacers 7 disposed opposite the flank of regulating member 18 is in
contact with
the flank of regulating member 18.
Moreover regulating members 12 and 18 and hollow cylinder 23 are tied via pull
stud 26
so that the axial movement of pull stud 26 causes similar movement of
regulating members
12 and 18 as well as hollow cylinder 23.
The rotary machine used as a pump functions the following way.
At start pull stud 26 is positioned so that regulating member 12 and
regulating member 18
are disposed at equal distances from the flanks of rotor 5 which they are
opposite and
hollow cylinder 23 is also at the midposition. For this purpose pull stud 26
is tied to them
as required.
When rotor 5 starts to rotate followers 25 of displacers 7 begin to slide over
the surfaces of
closed curved groove 24 and displacers 7 begin to reciprocate along the axis
of the rotor
1s rotation. Closed curved groove 24 is made so that the movement of each
displacer 7 per
one revolution of rotor 5 is characterized by the following cycle: displacer 7
having at the
start point sliding contact with the flank of regulating member 12 begins to
slide over its
flank towards partition 11 separating at the same time suction space 13 from
pumping
space 14 in the first working chamber. With further rotation of rotor 5 at a
certain moment
2o displacer 7 starts to go into rotor 5 and stops separating suction space 13
from pumping
space 14 i.e. loosing its sliding contact with regulating member 12.
But displacer 7 which is next to it at the same time slides over the flank of
regulating
member 9 separating suction space 13 from pumping space 14. The working fluid
confined
between two neighboring displacers 7 and also inside slots 6 wherein these
displacers 7 are
CA 02487334 2004-11-24
located, starts moving from suction space 13 to pumping space 14 which
displacers 7 come
to when rotor 5 rotates.
With further rotation of rotor 5, displacer 7 passes over partition 11 and
again begins to
come to regulating member 12. Then at some moment displacer 7 again touches -
,he flank
5 of regulating member 12 with its own flank and begins to slide over this
flank separating
suction space 13 from pumping space 14 as at the start moment.
The work cycle in the additional working chamber is almost the same, with the
only
difference being that displacer 7 which is in sliding contact with regulating
member 12
10 passes over partition 17 at the same moment and then when displacer 7
passes over
partition 11 it is a sliding contact with regulating member 18 separating
suction space 19
from pumping space 20. Suction space 19 of the additional working chamber at
the same
time is opposite pumping space 14 of the first working chamber and pumping
space 20 is
correspondingly opposite suction space 13. Since suction space 19 is connected
via
channel 21 to pumping space 14 and pumping space 20 is connected via channel
22 to
suction space 13 and regulating members 12 and 18 are at the midposition there
is no
working fluid flow through inlet port 12 and outlet port 16. This occurs
because the
amount of working fluid going into pumping space 14 is equal to the amount of
working
fluid going out off suction space 19 (these spaces are connected via channel
21) and the
amount of working fluid going out of suction space 13 is equal to the amount
of working
fluid going into pumping space 20 (these spaces are connected via channel 22).
When regulating member 12 is shifted by pull stud 26 to the end of its range
from rotor 5,
hollow cylinder 23 and regulating member 18 also move in the same direction.
Displacers
7 being in sliding contact with the flank of regulating member 12 slide out
from rotor 5 to
CA 02487334 2004-11-24
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the same axial extent as regulating member 12 and displacers 7 being in
sliding contact
with the flank of regulating member 18 correspondingly slide into rotor 5.
The working fluid delivery to pumping space 14 from suction space 13 increases
and the
intake of working fluid from suction space 19 and its flow to pumping space 20
decreases,
therefore the working fluid starts pumping into outlet port 16 and flowing out
of inlet port
15. In order to reverse the direction of the working fluid flow in the rotary
machine pull
stud 26 must be shifted to the other extreme position where regulating member
18 is
furthermost from rotor 5. When regulating member 18 is in this position the
direction of
the working fluid flow is reversed and the working fluid starts pumping now
into port 15
and flowing out of port 16.
It should be noted that when regulating members 12 and 18 are in these extreme
positions
the rotary machine works with maximum delivery and different directions of the
working
fluid pumping. When regulating members 12 and 18 approach the midposition,
delivery of
the rotary machine reduces to zero and begins to increase again when
regulating i.iembers
12 and 18 pass over the midposition but at the same time the direction of
working fluid
pumping reverses.
Since the working chambers located in the same axial direction opposite each
other are
connected to each other via the channels the working pressures in them are
equal and the
pressure forces acting on rotor 5 from these working chambers are completely
balanced.
When the rotary machine operates as a hydraulic motor it is possible to change
both speed
and direction of rotor 5 rotation by the positioning of pull stud 26 similar
to other
reversible rotary machines.
