U.S. patent application number 11/794459 was filed with the patent office on 2008-05-29 for rotary pump and multiple rotary pump employed thereof.
Invention is credited to Ki Chun Lee.
Application Number | 20080124228 11/794459 |
Document ID | / |
Family ID | 36615093 |
Filed Date | 2008-05-29 |
United States Patent
Application |
20080124228 |
Kind Code |
A1 |
Lee; Ki Chun |
May 29, 2008 |
Rotary Pump And Multiple Rotary Pump Employed Thereof
Abstract
A rotary pump is provided in which a drive motor is provided
such that an output shaft of the drive motor is placed at an offset
position, so that a rotational speed of the pump can be changed to
a high or low speed. Furthermore, rigid balls or needle roller
bearings are used in each rotor unit such that each eccentric
rotary body is in rolling contact with a circumferential inner
surface of each cylindrical housing, thus reducing friction between
them, thereby ensuring smooth rotation of the rotor units. In
addition, a space, which is defined between each cylindrical
housing and each eccentric rotary body, prevents a cross-plate from
being damaged due to torsional stress and tensile force, thereby
ensuring superior durability of the pump.
Inventors: |
Lee; Ki Chun; (Seoul,
KR) |
Correspondence
Address: |
SEED INTELLECTUAL PROPERTY LAW GROUP PLLC
701 FIFTH AVE, SUITE 5400
SEATTLE
WA
98104
US
|
Family ID: |
36615093 |
Appl. No.: |
11/794459 |
Filed: |
November 23, 2005 |
PCT Filed: |
November 23, 2005 |
PCT NO: |
PCT/KR05/03968 |
371 Date: |
November 19, 2007 |
Current U.S.
Class: |
417/271 |
Current CPC
Class: |
F04C 2/06 20130101; F04C
11/00 20130101; F04C 11/001 20130101; F04C 15/0061 20130101 |
Class at
Publication: |
417/271 |
International
Class: |
F04B 27/00 20060101
F04B027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 28, 2004 |
KR |
10-2004-0114504 |
Jan 5, 2005 |
KR |
10-2005-0001006 |
Sep 28, 2005 |
KR |
10-2005-0090212 |
Sep 28, 2005 |
KR |
10-2005-0090214 |
Claims
1. A rotary pump comprising: a drive motor; upper and lower
chambers; a pair of rotor units respectively provided in the upper
and lower chambers such that the pair of rotor units are configured
to be driven by the drive motor and moving along inner surfaces of
the chambers; a cross-plate integrally connecting the pair of rotor
units to each other, wherein each of the rotor units includes: a
cylindrical housing; an eccentric rotary body installed and
eccentrically rotatable in the cylindrical housing; and means for
reducing friction between the eccentric rotary body and the
cylindrical housing when the eccentric rotary body rotates within
the cylindrical housing.
2. The rotary pump as claimed in claim 1, wherein the cylindrical
housing includes a cylindrical shape with a diameter smaller than
an inner diameter of each chamber, with a plurality of bearing
seats formed in a circumferential inner surface of the cylindrical
housing, and a space defined in the cylindrical housing, the
eccentric rotary body having a diameter smaller than the inner
diameter of the cylindrical housing and eccentrically fitted over a
rotatable shaft, and the means for reducing friction includes a
plurality of bearing members respectively seated into the plurality
of bearing seats of the cylindrical housing.
3. The rotary pump as claimed in claim 2, wherein the bearing seats
each have a depth, respective magnitudes of the depths sequentially
decreasing from a 12 o'clock position to a 3 o'clock position,
being substantially constant from the 3 o'clock position to a 9
o'clock position, and sequentially increasing from the 9 o'clock
position to the 12 o'clock position, the clock positions being
positioned with respect to the circumferential inner surface of the
cylindrical housing.
4. The rotary pump as claimed in claim 3, wherein when the
cylindrical housing is sectioned into a center side half-circle
portion which is adjacent the cross-plate and a remaining outside
half-circle portion, the bearing seats formed in the center side
half-circle portion of the cylindrical housing have a most shallow
depth with respect to the other bearing seats, the center side
half-circle portion extending from the 3 o'clock position to the 9
o'clock position.
5. The rotary pump as claimed in claim 2, wherein the bearing seats
each have a diameter, respective magnitudes of the diameters
sequentially increasing from a 12 o'clock position to a 3 o'clock
position, being substantially constant from the 3 o'clock position
to a 9 o'clock position, and sequentially decreasing from the 9
o'clock position to the 12 o'clock position, the clock positions
being positioned with respect to the circumferential inner surface
of the cylindrical housing.
6. The rotary pump as claimed in claim 5, wherein when the
cylindrical housing is sectioned into a center side half-circle
portion which is adjacent the cross-plate and a remaining outside
half-circle portion, the bearing seats formed in the center side
half-circle portion of the cylindrical housing have a most largest
diameter with respect to the other bearing seats, the center side
half-circle portion extending from the 3 o'clock position to the 9
o'clock position.
7. The rotary pump as claimed in claim 1, wherein the cylindrical
housing includes a cylindrical shape with a diameter smaller than
an inner diameter of each chamber, with a space defined in the
cylindrical housing, the eccentric rotary body having a diameter
smaller than the inner diameter of the cylindrical housing and
eccentrically fitted over a rotatable shaft, with a plurality of
bearing seats formed in a circumferential outer surface of the
eccentric rotary body, and the means for reducing friction includes
a plurality of bearing members respectively seated into the
plurality of bearing seats of the eccentric rotary body.
8. The rotary pump as claimed in claim 7, wherein the bearing seats
each have a depth, respective magnitudes of the depths sequentially
increasing from a 12 o'clock position to a 3 o'clock position,
sequentially decreasing from the 3 o'clock position to a 6 o'clock
position, sequentially increasing from the 6 o'clock position to a
9 o'clock position, and sequentially decreasing from the 9 o'clock
position to the 12 o'clock position, the clock positions being
positioned with respect to the circumferential outer surface of the
eccentric rotary body.
9. The rotary pump as claimed in claim 8, wherein when the
cylindrical housing is sectioned into a left side half-circle
portion and a right side half-circle portion by a line which is
extended along a longitudinal direction of the cross-plate, the
left side half-circle portion and the right side half-circle
portion are symmetrically formed along the circumferential outer
surface of the eccentric rotary body.
10. The rotary pump as claimed in claim 8, wherein the bearing
seats each have a diameter, respective magnitudes of the diameters
sequentially decreasing from a 12 o'clock position to a 3 o'clock
position, sequentially increasing from the 3 o'clock position to a
6 o'clock position, sequentially decreasing from the 6 o'clock
position to a 9 o'clock position, and sequentially increasing from
the 9 o'clock position to the 12 o'clock position, the clock
positions being positioned with respect to the circumferential
outer surface of the eccentric rotary body.
11. The rotary pump as claimed in claim 10, wherein when the
cylindrical housing is sectioned into a left side half-circle
portion and a right side half-circle portion by a line which is
extended along a longitudinal direction of the cross-plate, the
left side half-circle portion and the right side half-circle
portion are symmetrically formed along the circumferential outer
surface of the eccentric rotary body.
12. The rotary pump to as claimed in claim 1, wherein the means for
reducing friction includes ball bearings or needle roller bearings
positioned between the cylindrical housing and the eccentric rotary
body.
13. The rotary pump as claimed in claim 1, wherein the rotary pump
further comprises an overload prevention unit provided on an output
shaft of the drive motor in order to prevent the drive motor from
overloading.
14. The rotary pump as claimed in claim 13, wherein the overload
prevention unit comprises: a plurality of ball seats formed in a
circumferential outer surface of an end of the output shaft of the
drive motor; a coupler having a receiving space in which the output
shaft is inserted and a plurality of ball insertion holes formed
along a sidewall of the coupler at positions corresponding to the
ball seats; and a cover ring fitted over a circumferential outer
surface of the coupler to prevent balls from being undesirably
removed, wherein the balls are inserted into the ball insertion
holes and seated into the ball seats, and the cover ring surrounds
the balls, so that, when an overload is applied to the clutch unit,
the balls push outwards and deform the cover ring thus interrupting
power transmission.
15. The rotary pump as claimed in claim 4, wherein a motor gear is
formed on a circumferential outer surface of the coupler, wherein
the motor gear is a helical gear.
16. The rotary pump as claimed in claim 1, wherein the rotary pump
further comprises a power transmitting, unit in order to transmit
power from the drive motor to the rotor units, wherein a rotational
speed of the drive motor is changed by the power transmitting
unit.
17. The rotary pump as claimed in claim 16, wherein the power
transmitting unit comprises: a pair of rotatable shafts which are
parallel to each other; a drive gear rotatable engaging with a
motor gear formed on an end of an output shaft of the drive motor,
and fitted on either one of the rotatable shafts; a first main gear
fitted on either one of the rotatable shafts which is rotatable
together with the drive gear; and a second main gear engaging with
the first main gear and fitted on the other rotatable shaft wherein
the first main gear and the second main gear are rotatable in an
opposite direction to each other.
18. The rotary pump as claimed in claim 16, wherein the power
transmitting unit comprises: a pair of rotatable shafts which are
parallel to each other; a first transmitting gear engaging with a
motor gear formed on an end of an output shaft of the drive motor
and idly inserted on either one of the rotatable shafts, the first
transmitting gear being integrally formed with a subsidiary
transmitting gear which has a diameter smaller than the diameter of
the first transmitting gear; a second transmitting gear fitted on
either one of the rotatable shafts or the other of the rotatable
shafts; a first main gear fitted on the rotatable shaft which is
rotatable together with the drive gear; a second main gear engaging
with the first main gear and fitted on the rotatable shaft on which
the first main gear is not fitted; and a plurality of driven gears
arranging between the subsidiary transmitting gear and the second
transmitting gear and transmitting power from the subsidiary
transmitting gear to the second transmitting gear, the driven gears
being integrally formed with respective subsidiary driven gears
which have a diameter smaller than the diameter of the driven
gears, wherein each of the driven gears is idly inserted on the
rotatable shafts such that a downstream driven gear is rotatably
engaged with an upstream subsidiary driven gear, and the first main
gear and the second main gear are rotatable in an opposite
direction to each other.
19. The rotary pump as claimed in claim 16, wherein the power
transmitting unit comprises: a pair of the rotatable shafts which
are parallel to each other; a first transmitting gear engaging with
a motor gear formed on an end of an output shaft of the drive motor
and idly inserted on either one of the rotatable shafts, the first
transmitting gear being integrally formed with a subsidiary
transmitting gear which has a diameter larger than the diameter of
the first transmitting gear; a second transmitting gear fitted on
either one of the rotatable shafts or the other of the rotatable
shafts; a first main gear fitted on the rotatable shafts which is
rotatable together with the drive gear; a second main gear engaging
with the first main gear and fitted on the rotatable shaft on which
the first main gear is not fitted; and a plurality of driven gears
arranging between the subsidiary transmitting gear and the second
transmitting gear and transmitting power from the subsidiary
transmitting gear to the second transmitting gear, the driven gears
being integrally formed with respective subsidiary driven gears
which have a diameter larger than the diameter of the driven gears,
wherein each of the driven gears is idly inserted on the rotatable
shafts such that a downstream driven gear is rotatably engaged with
an upstream subsidiary driven gear, and the first main gear and the
second main gear are rotatable in an opposite direction to each
other.
20. A rotary pump comprising: a drive motor; a plurality of upper
and lower chambers which are laterally arranged to each other; a
plurality of pairs of rotor units respectively provided in the
respective upper and lower chambers such that the pairs of rotor
units are configured to be driven by the drive motor and moving
along inner surfaces of the chambers; and a cross-plate integrally
connecting the pairs of rotor units to each other, wherein each of
the rotor units includes: a cylindrical housing; an eccentric
rotary body installed and eccentrically rotatable in the
cylindrical housing; and means for reducing friction between the
eccentric rotary body and the cylindrical housing when the
eccentric rotary body rotates within the cylindrical housing.
Description
CROSS-REFERENCE(S) TO RELATED APPLICATION(S)
[0001] The present application is based on, and claims priority
from, Korean Patent Application Serial Numbers 2004-0114504,
2005-0001006, 2005-0090212, and 2005-0090214.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates, in general, to rotary pumps
which pump fluid using suction force of rotor units that are
rotated by drive motors and, more particularly, to a multiple
rotary pump in which a drive motor is provided such that an output
shaft of the drive motor is placed at an offset position, so that a
rotational speed of the pump can be changed to a high or low speed,
and in which an eccentric rotary body is moved in a space defined
in each rotor unit, thus preventing a cross-plate from being
damaged, and which ensures smooth rotation of the rotor units using
a bearing means.
[0004] 2. Description of the Related Art
[0005] As well known to those skilled in the art, pumps are
machines which move fluid to another place, for example, from a low
position to a high position.
[0006] However, conventional pumps have many problems. Hereinafter,
a representative conventional pump will be explained, and problems
experienced with this pump will be described.
[0007] FIG. 1 illustrates a rotary pump in which an upper rotor
unit 2, which is provided in an upper chamber 1, is coupled to a
lower rotor unit 4, which is provided in a lower chamber 3, through
a cross-plate 5.
[0008] As shown in FIG. 1, in the conventional rotary pump, when
the upper rotor unit 2 and the lower rotor unit 4 are placed
upright, the distance between the centers of the upper and lower
rotor units 2 and 4, which are offset from the chambers, is
shortest.
[0009] In other words, the distance between the upper rotor unit 2
and the lower rotor unit 4 becomes shortest.
[0010] As shown in the second view of FIG. 1, when the upper rotor
unit 2 and the lower rotor unit 4 are placed in an oblique
direction, the distance between the centers of the upper and lower
rotor units 2 and 4, which are offset from the chambers, is
longest.
[0011] In other words, the distance between the upper rotor unit 2
and the lower rotor unit 4 becomes longest.
[0012] For example, as shown in FIG. 1, when the upper rotor unit 2
and the lower rotor unit 4 are placed upright, the distance between
the centers of the upper and lower rotor units 2 and 4, which are
offset from the chambers, is 6.90 inches (175.2 mm).
[0013] At this time, the distance between the upper rotor unit 2
and the lower rotor unit 4 is 2.41 inches (61.2 mm). As shown in
FIG. 1, when the upper rotor unit 2 and the lower rotor unit 4 are
placed in an oblique direction, the distance between the centers of
the upper and lower rotor units 2 and 4, which are offset from the
chambers, is 6.98 inches (177.2 mm).
[0014] At this time, the distance between the upper rotor unit 2
and the lower rotor unit 4 is 2.49 inches (63.2 mm).
[0015] Here, if the cross-plate 5, which couples the upper rotor
unit 2 to the lower rotor unit 4, is a rigid body, the structure
and operation of the rotary pump shown in FIG. 1 cannot be
realized. In other words, the length of the cross-plate 5 must be
varied depending on the positions of the rotor units 2 and 4.
[0016] To solve the above-mentioned problem, a rotary pump was
proposed in Korean Patent Application No. 1994-010299, entitled
"double cylindrical pump."As shown in FIG. 2, this pump is
constructed such that a cross-plate 3 is inserted into a sliding
slot 2 formed in a circumferential outer surface of a first sliding
body 1 (hereinafter, referred to as an upper rotor unit), and the
cross-plate 3 is removably coupled to the upper rotor unit 1 and is
integrally coupled to a second sliding body 4 (hereinafter,
referred to as a lower rotor unit).
[0017] Thus, when the upper rotor unit 1 and the lower rotor unit 4
are placed in an oblique direction, the cross-plate 3 slides in the
sliding slot 2 of the upper rotor unit 1, so that the distance
between the upper rotor unit 1 and the lower rotor unit 4 can be
varied. However, in this pump, in which the distance between the
upper and lower rotor units 1 and 4 is varied by the cross-plate 3
moving in the sliding slot 2 of the upper rotor unit 1, because the
cross-plate 3 slides in the sliding slot 2 while the upper and
lower rotor units 1 and 4 are rotating, there is a likelihood of
the cross-plate 3 being undesirably removed from the upper rotor
unit 1. Furthermore, in the case that this pump structure is
applied to a multiple rotary pump, because rotational force
(torque) is applied to the upper rotor unit 1 prior to sliding
movement of the cross-plate 3 in the sliding slot 2, torsional
stress is applied to offset shafts which rotate the upper rotor
unit 1.
[0018] Of course, this phenomenon may cause breakage of the offset
shafts, the rotor units 1 and 4 or the cross-plate 3.
[0019] To solve this problem, a method in which eccentric gears are
used to constantly maintain the distance between upper and lower
rotor units has been used. However, in the case that this method is
applied to a multiple rotary pump, the offset shafts rotate the
upper rotor unit in a clockwise direction and rotate the lower
rotor unit in a counterclockwise direction using the eccentric
gears, thus generating torsional stress. As such, the eccentric
gears can be used in a rotary pump having a single structure, but,
in the case that the eccentric gears are used in a multiple rotary
pump, because the orientations of the rotor units coupled to the
shafts are different, an acceleration section is varied by the
eccentricity. Thus, the possibility of breakage of the rotor units
is increased.
BRIEF SUMMARY
[0020] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the prior art, and an object
of the present invention is to provide a multiple rotary pump which
pumps fluid using suction force of rotor units rotated by a drive
motor, and in which the drive motor is provided such that an output
shaft of the drive motor is placed at an offset position, so that a
rotational speed of the pump can be changed to high or low speed,
and in which an eccentric rotary body is moved in a space defined
in each rotor unit, thus preventing a cross-plate from being
damaged, and which ensures smooth rotation of the rotor units using
a bearing means.
[0021] In one embodiment, the present invention provides a rotary
pump which has a drive motor and upper and lower chambers and pumps
fluid both using rotor units moving along inner surfaces of the
chambers and using a cross-plate. The rotary pump comprises: a
drive motor provided at a predetermined position such that an
output shaft thereof is disposed at an offset position, with an
overload prevention unit provided on an end of the output shaft,
the overload preventing unit having a helical motor gear; a clutch
unit coupled to an end of the overload prevention unit; upper and
lower chambers; rotor units provided in the respective upper and
lower chambers such that power is transmitted through the clutch
unit to the rotor units, each of the rotor units having an
eccentric rotary body installed in each rotor unit and
eccentrically rotated by each of a pair of rotating shafts and,
with bearing means provided in each of the rotor units. When power
of the drive motor is transmitted, the number of revolutions of the
drive motor is changed by the clutch unit, and the rotor units move
along inner surfaces of the chambers using the power transmitted
through the clutch unit, thus pumping fluid from the chambers.
[0022] The clutch unit, is coupled to the overload prevention unit,
and may comprise: a first gear engaging with the helical motor
gear, which is eccentrically positioned, the first gear being
rotatably fitted over one of the rotating shafts, which is placed
at a position opposite a direction in which the helical motor gear
is offset, and a first subsidiary gear having a diameter smaller
than a diameter of the first gear and integrally provided beneath
the first gear; a second gear having a larger diameter and engaging
with the first subsidiary gear, the second gear being rotatably
fitted over the other of the rotating shafts, and a second
subsidiary gear having a diameter smaller than the diameter of the
second gear and integrally provided beneath the second gear; a
third gear having a larger diameter and engaging with the second
subsidiary gear, the third gear being rotatably fitted over the one
of the rotating shafts, and a third subsidiary gear having a
diameter smaller than the diameter of the third gear and integrally
provided beneath the third gear; a fourth gear having a larger
diameter and engaging with the third subsidiary gear, the fourth
gear being rotatably fitted over the other of the rotating shafts,
and a fourth subsidiary gear having a diameter smaller than the
diameter of the fourth gear and integrally provided beneath the
fourth gear; a fifth gear having a larger diameter and engaging
with the fourth subsidiary gear, the fifth gear being rotatably
fitted over the one of the rotating shafts, and a fifth subsidiary
gear having a diameter smaller than the diameter of the fifth gear
and integrally provided beneath the fifth gear; a drive gear having
a larger diameter and engaging with the fifth subsidiary gear, the
drive gear being fitted over and locked to the other of the
rotating shafts using a key; and first and second main gears having
a same diameter and respectively fitted over and locked to the
rotating shafts and using keys, respectively. When the first,
second, third, fourth and fifth gears and the first, second, third,
fourth and fifth subsidiary gears are fitted over the first and
second shafts, bearings are interposed between the rotating shafts
and the gears such that the gears are rotated at relatively low
speeds with respect to the rotating shafts, and when the first and
second main gears and are rotated at low speeds by the power
transmitted from the drive gear, the rotor units are rotated at low
speeds.
[0023] In another embodiment of the clutch unit coupled to the
overload prevention unit, the clutch unit comprises: a first gear
engaging with the helical motor gear, which is eccentrically
positioned, the first gear being rotatably fitted over one of the
rotating shafts, which is placed at a position opposite a direction
in which the helical motor gear is offset, and a first subsidiary
gear having a diameter larger than a diameter of the first gear and
integrally provided beneath the first gear; a second gear having a
smaller diameter and engaging with the first subsidiary gear, the
second gear being rotatably fitted over the other of the rotating
shafts, and a second subsidiary gear having a diameter larger than
the diameter of the second gear and integrally provided beneath the
second gear; a third gear having a smaller diameter and engaging
with the second subsidiary gear, the third gear being rotatably
fitted over the one of the rotating shafts, and a third subsidiary
gear having a diameter larger than the diameter of the third gear
and integrally provided beneath the third gear; a fourth gear
having a smaller diameter and engaging with the third subsidiary
gear, the fourth gear being rotatably fitted over the other of the
rotating shafts, and a fourth subsidiary gear having a diameter
larger than the diameter of the fourth gear and integrally provided
beneath the fourth gear; a drive gear having a smaller diameter and
engaging with the fourth subsidiary gear, the drive gear being
fitted over and locked to the one of the rotating shafts using a
key; and first and second main gears having a same diameter and
respectively fitted over and locked to the rotating shafts using
keys. When the first, second, third and fourth gears and the first,
second, third and fourth subsidiary gears are fitted over the first
and second shafts, bearings are interposed between the rotating
shafts and the gears such that the gears are rotated at relatively
high speeds with respect to the rotating shafts, and when the first
and second main gears are rotated by the power transmitted from the
drive gear, the rotor units are rotated at high speeds.
[0024] Each of the rotor units may comprise: a cylindrical housing
having a cylindrical shape with a diameter smaller than an inner
diameter of each chamber, with a plurality of bearing seats formed
in a circumferential inner surface of the cylindrical housing, and
a space defined in the cylindrical housing; the eccentric rotary
body having a diameter smaller than the inner diameter of the
cylindrical housing and eccentrically fitted over each of the
rotating shafts; and the bearing means seated into the bearing
seats of the cylindrical housing. Both the cylindrical housing and
the eccentric rotary body are provided in each of the upper and
lower chambers, and the two cylindrical housings are coupled to
each other through the cross-plate and are eccentrically
rotated.
[0025] In another embodiment, each rotor unit may comprise: a
cylindrical housing having a cylindrical shape with a diameter
smaller than an inner diameter of each chamber, with a space
defined in the cylindrical housing; the eccentric rotary body
having a diameter smaller than the inner diameter of the
cylindrical housing and eccentrically fitted over each of the
rotating shafts, with a plurality of bearing seats formed in a
circumferential outer surface of the eccentric rotary body; and the
bearing means seated into the bearing seats of the eccentric rotary
body. Both the cylindrical housing and the eccentric rotary body
are provided in each of the upper and lower chambers, and the two
cylindrical housings are coupled to each other through the
cross-plate and are eccentrically rotated.
[0026] As described above, in the rotary pump according to an
embodiment of the present invention, rigid balls or needle roller
bearings serving as a bearing means are used in each rotor unit
such that each eccentric rotary body is in rolling contact with the
a circumferential inner surface of each chamber, thus reducing
friction between them, thereby ensuring smooth rotation of the
rotor units.
[0027] Furthermore, in embodiments of the present invention, a
space is defined between the chamber and the eccentric rotary body,
thus solving a conventional problem in that a cross-plate is
damaged by torsional stress and tensile force, thereby ensuring
superior durability of the pump.
[0028] As well, even if an overload is applied to the rotor units
or a clutch unit, because an overload prevention unit is provided,
the clutch unit is prevented from being damaged, thus further
enhancing the durability.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0029] FIG. 1 is a view showing a rotor unit of a conventional
rotary pump;
[0030] FIG. 2 is a view showing a cross-plate inserted into a slide
slot of a rotor unit of another conventional pump;
[0031] FIG. 3 is a view showing an operation of a rotor unit
according to one embodiment;
[0032] FIG. 4 is a schematic view showing a reason that a
cross-plate must be lengthened;
[0033] FIG. 5 is a sectional view showing a first embodiment of a
clutch unit of the present invention;
[0034] FIG. 6 is a sectional view showing a second embodiment of a
clutch unit of the present invention;
[0035] FIG. 7 is a sectional view showing a third embodiment of a
clutch unit of the present invention;
[0036] FIG. 8 is a sectional view showing a fourth embodiment of a
clutch unit of the present invention;
[0037] FIGS. 9 and 10 are views showing an operation of a rotor
unit according to one embodiment;
[0038] FIG. 11 is a view showing an enlargement of a first
embodiment of a rotor unit of the present invention;
[0039] FIG. 12 is a view of a cylindrical housing according to the
first embodiment of the rotor unit of the present invention;
[0040] FIG. 13 is a schematic view illustrating an operation of the
rotor unit according to the first embodiment of the present
invention;
[0041] FIG. 14 is a view showing a modification of the rotor unit
according to the first embodiment of the present invention;
[0042] FIG. 15 is a view showing an enlargement of a second
embodiment of the rotor unit of the present invention;
[0043] FIG. 16 is a view showing an eccentric rotary body according
to the second embodiment of the rotor unit of the present
invention;
[0044] FIG. 17 is a view showing a modification of the rotor unit
according to the second embodiment of the present invention;
[0045] FIG. 18 is a schematic view illustrating an operation of the
rotor unit according to the second embodiment of the present
invention;
[0046] FIG. 19 is schematic views showing installation of a bearing
means according to one embodiment of the present invention;
[0047] FIG. 20 is schematic views showing installation of the
bearing means according to one embodiment of the present
invention;
[0048] FIG. 21 is a plan view of a pump according to one embodiment
of the present invention;
[0049] FIG. 22 is a view showing a duplex pump according to one
embodiment of the present invention;
[0050] FIG. 23 is a view showing a triplex pump according to one
embodiment of the present invention;
[0051] FIG. 24 is a view showing a quadruple pump according to one
embodiment of the present invention;
[0052] FIG. 25 is a view showing an example of a piping structure
of a pump according to one embodiment of the present invention;
[0053] FIG. 26 is a view showing another example of a piping
structure of a pump according to one embodiment of the present
invention;
[0054] FIG. 27 is a view showing a further example of a piping
structure of a pump according to one embodiment of the present
invention;
[0055] FIG. 28 is a view showing yet another example of a piping
structure of a pump according to one embodiment of the present
invention;
[0056] FIG. 29 is a sectional view showing the construction of the
quadruple pump according to one embodiment of the present
invention;
[0057] FIG. 30 is a perspective view of an overload prevention unit
of one embodiment of the present invention; and
[0058] FIG. 31 is a sectional view showing the overload prevention
unit coupled to an output shaft of a drive motor according to one
embodiment of the present invention.
DETAILED DESCRIPTION
[0059] According to one embodiment, a rotary pump includes a drive
motor and upper and lower chambers, in which a pumping operation is
executed by movement both of rotor units, which rotate along the
inner surface of the chambers, and of a cross-plate. The rotary
pump further includes an eccentric rotary body in each rotor unit,
and a gap is defined between the rotor unit and the eccentric
rotary body. Thanks to the gap, embodiments of the present
invention do not require a variable length of the cross-plate,
unlike the conventional art. Furthermore, another special feature
of the present invention is characterized in that a rotational
speed can be changed between a high speed and a low speed.
Hereinafter, the present invention will be described in detail with
reference to the attached drawings. To explain the present
invention more clearly, an operation of the rotor units will be
described with reference to FIG. 3.
[0060] According to one embodiment, a rotary pump includes a pair
of rotor units 200 which rotate in two chambers 30, which can be
circular in shape.
[0061] As shown in FIG. 3, an upper rotor unit 200 (placed at an
upper position when viewing the drawing) is rotated in a clockwise
direction. A lower rotor unit 200 (placed at a lower position when
viewing the drawing) is rotated in a counterclockwise direction.
Therefore, as sequentially shown in FIG. 3, first, the rotor units
200 are oriented in a vertical direction while the upper rotor unit
200 contacts the uppermost point of an upper chamber 30. Next, the
upper rotor unit 200 is rotated at 90.degree. in a clockwise
direction, so that the contact surface of the upper rotor unit 200
moves to a portion of the upper chamber 30 (placed at the upper
position when viewing the drawing) which is spaced apart from the
uppermost point at 90.degree.. Of course, at this time, the lower
rotor unit 200 (placed at the lower position when viewing the
drawing) is rotated at 90.degree. in a counterclockwise direction
so that the contact surface thereof moves to a portion of the inner
surface of the lower chamber 30 (placed at the lower position when
viewing the drawing) which is spaced apart from the uppermost point
at 270.degree..
[0062] Subsequently, the upper rotor unit 200 is rotated in a
clockwise direction until it reaches a portion of the upper chamber
30 spaced apart from the uppermost point at 180.degree.. At this
time, the lower rotor unit is rotated in a counterclockwise
direction until it reaches a portion of the inner surface of the
lower chamber 30 spaced apart from the uppermost point at
180.degree..
[0063] Continuously, the upper rotor unit 200 is rotated in a
clockwise direction until it reaches a portion of the inner surface
of the upper chamber 30 spaced apart from the uppermost point at
270.degree.. Simultaneously, the lower rotor unit is rotated in a
counterclockwise direction until it reaches a portion of the inner
surface of the lower chamber 30 spaced apart from the uppermost
point at 90.degree.. Of course, after that, the rotor units 200 are
returned to the first stage. This process is continuously
repeated.
[0064] In another embodiment, unlike the above case in which the
upper rotor unit 200 is rotated in a clockwise direction while the
lower rotor unit 200 is rotated in a counterclockwise direction,
the upper rotor unit 200 may be rotated in a counterclockwise
direction, and the lower rotor unit 200 may be rotated in a
clockwise direction.
[0065] In either case, by such rotation, fluid is drawn into the
chambers 30 through an inlet (BC) and is discharged through an
outlet (BD).
[0066] Hereinafter, the reason that a cross-plate 207 that couples
the upper rotor unit 200 to the lower rotor unit 200 must be
lengthened and shortened when the rotor units 200 are rotated in
the conventional art, will be explained with reference to FIG.
4.
[0067] For ease of description, in this drawing, the diameter of
each rotor unit 200 is greatly reduced.
[0068] As shown in the drawing, in the conventional art, when the
upper rotor unit 200 and the lower rotor unit 200 are disposed in a
vertical line, the length of the cross-plate is AB and the same as
the length AC (AB=AC).
[0069] Meanwhile, when the upper rotor unit 200 is rotated in a
clockwise direction and reaches the portion of the inner surface of
the upper chamber 30 spaced apart from the uppermost point at
90.degree., the lower rotor unit 200 is rotated in a
counterclockwise direction and reaches the portion of the inner
surface of the lower chamber 30 spaced apart from the uppermost
point at 270.degree..
[0070] At this time, the length of the cross-plate is AK.
Therefore, as demonstrated in the Pythagorean Theorem in that the
length of the hypotenuse of a right-angled triangle is longest, the
length of the cross-plate must be lengthened by any method.
[0071] For this, the conventional art has the structure such that
the length of the cross-plate is varied while the diameter of the
rotor unit 200 is constant.
[0072] Meanwhile, as the problems of the conventional art have
already been described above, further explanation is deemed
unnecessary. To solve the problems of the conventional art, in
embodiments of the present invention, an eccentric rotary body 220
is provided in each rotor unit 200, and a space is defined around
the eccentric rotary body in the rotor unit 200. The description of
these is as follows.
[0073] According to one embodiment, shown in FIG. 5 a drive motor
10 is provided at a predetermined position such that an output
shaft 11 thereof is disposed at an eccentric position. An overload
prevention unit 20 having a helical motor gear 12 is provided
toward an end of the output shaft 11. A clutch unit 100 is provided
on an end of the overload prevention unit 20. Furthermore, chambers
30 are provided at upper and lower positions. The rotor units 200,
which receive driving force from the clutch unit 100, are installed
in the chambers 30. The eccentric rotary body 220, which has a
bearing means 210 and is rotated by a rotating shaft S1 or S2, is
installed in each rotor unit 200.
[0074] Therefore, while power of the drive motor 10 is transmitted
to the rotating shafts S1 and S2, revolutions of the rotating
shafts S1 and S2 are changed by the clutch unit 100. Fluid is
pumped outside of the chambers 30 by pumping-rotation of the rotor
units 200.
[0075] In detail, the drive motor 10 is coupled to the pump such
that the output shaft 11 thereof is positioned toward a side of the
center of the pump, that is, is eccentrically positioned with
respect to the pump. Furthermore, the helical motor gear 12 is
provided toward the end of the output shaft 11 to increase rotating
friction.
[0076] The clutch unit 100 is coupled to the helical motor gear 12.
In embodiments of the present invention, a high-speed clutch unit
100 or a low-speed clutch unit 100, which will be explained later
herein, can be selectively provided.
[0077] According to one embodiment, rotational force of the drive
motor 10 is transmitted to the rotating shafts S1 and S2 through
the clutch unit 100, after the rotational speed is changed to a
high or low speed by the clutch unit 100. The eccentric rotary
bodies 220 are rotated by the above-mentioned rotational force. At
this time, the eccentric rotary bodies 220 can be smoothly rotated
by the bearing means 210 during the fluid pumping operation.
[0078] Hereinafter, embodiments of the clutch unit 100 used in the
present invention will be described.
[0079] In the case of a first embodiment, as shown in FIG. 5, the
clutch unit 100 is coupled to the overload prevention unit 20. In
detail, a low-speed drive gear 110, which engages with the helical
motor gear 12 that is eccentrically positioned, is fitted over the
rotating shaft S2, which is placed at a position opposite the
direction in which the helical motor gear 12 is offset. The
low-speed drive gear 110 is locked to the rotating shaft S2 by a
key K. A first main gear 111 is fitted over the rotating shaft S2
below the low-speed drive gear 110 while being locked to the
rotating shaft S2 by a key K.
[0080] Furthermore, a second main gear 112, which engages with the
first main gear 111, is fitted over the other rotating shaft S1 and
locked to the rotating shaft S1 by a key.
[0081] Therefore, the first main gear 111 is rotated by rotation of
the low-speed drive gear 110 at a low speed. The second main gear
112, which engages with the first main gear 111, is rotated in an
opposite direction.
[0082] As shown in FIG. 5, the drive motor 10 is provided such that
the output shaft 11 thereof is inserted into the pump at an offset
position, in detail, at a position offset towards the upper rotor
unit 200 (located on the right when viewing the drawing).
[0083] Of course, the output shaft 11 may be eccentrically placed
such that it is offset towards the lower rotor unit 200 (located on
the left when viewing the drawing).
[0084] As shown in this embodiment, the reason that the output
shaft 11 is placed such that it is offset towards the upper rotor
unit 200 is to construct the rotary pump such that the rotational
speed of the rotating shafts S1 and S2 can be changed to a high or
low speed. If the output shaft 11 is offset towards the upper rotor
unit 200, a space defined between the output shaft 11 and the lower
rotor unit 200 (located on the left when viewing the drawing) is
greater than a space defined between the output shaft 11 and the
upper rotor unit 200.
[0085] Therefore, as shown in FIG. 5, the gear having a larger
diameter can be applied in the larger space.
[0086] As well known in the art, when a small gear rotates a large
gear, the rotational speed of the shaft of the large gear becomes
slower than that of the small gear. Therefore, in the first
embodiment of FIG. 5, the low-speed drive gear 110 is rotated at a
low speed. In other words, when the drive motor 10 is rotated, the
low-speed drive gear 110, having the large diameter, is rotated at
a low speed.
[0087] Of course, because the low-speed drive gear 110 is locked to
the rotating shaft S2 by the key K, the rotating shaft S2 and the
low-speed drive gear 110 are rotated at the same angular speed.
[0088] Furthermore, the first main gear 111 is locked to the
rotating shaft S2 by the key K below the low-speed drive gear 110.
Therefore, revolutions of the low-speed drive gear 110 are also the
same as that of the rotating shaft S2.
[0089] Furthermore, the second main gear 112, which engages with
the first main gear 111, is locked to the other rotating shaft S1
by a key. The rotating shafts S1 and S2, which are coupled to the
clutch unit 100, are coupled to the respective eccentric rotary
bodies 220 such that each eccentric rotary body 220 is
eccentric.
[0090] As a result, the rotating shafts S1 and S2 are rotated in
directions opposite each other and rotate the rotor units 200, thus
pumping fluid at a low speed.
[0091] A pump according to embodiments of the present invention may
be used for pumping air as well as fluid, that is, may be applied
to a pneumatic compressor.
[0092] Meanwhile, FIG. 6 illustrates a high-speed type of a second
embodiment of the clutch unit 100 of the present invention.
[0093] In this embodiment, a high-speed drive gear 120 is provided
at the narrower side in the spaces defined between the rotating
shafts S1 and S2 and the output shaft 11 of the drive motor 10,
which is offset to the right when viewing the drawing. The
high-speed drive gear 120 has a small diameter so that it can be
rotated at a high speed.
[0094] A construction of this embodiment will be explained with
reference to FIG. 6. In the second embodiment of the clutch unit
100 coupled to the overload prevention unit 20, the high-speed
drive gear 120, which engages with the helical motor gear 12 that
is eccentrically positioned, is fitted over the rotating shaft S1,
which is placed at a predetermined position in the direction in
which the helical motor gear 12 is offset. The high-speed drive
gear 120 is locked to the rotating shaft S1 by a key K. A first
main gear 121 is fitted over the rotating shaft S1 below the
high-speed drive gear 120 while being locked to the rotating shaft
S2 by a key K.
[0095] Furthermore, a second main gear 122, which engages with the
first main gear 121, is fitted over the other rotating shaft S2 and
locked to the rotating shaft S2 by a key K.
[0096] Therefore, the first main gear 121 is rotated by rotation of
the high-speed drive gear 120 at a high speed. The second main gear
122, which engages with the first main gear 121, is rotated in an
opposite direction.
[0097] The operation of the clutch unit 100 according to this
embodiment will be explained with reference to FIG. 6. When the
drive motor 10 is operated, the high-speed drive gear 120, which
engages with the helical motor gear 12 coupled to the output shaft
11 of the drive motor 10, is rotated at a high speed.
[0098] Of course, the rotational speed of the high-speed drive gear
120 is slower than that of the output shaft of the drive motor 10.
As such, when the high-speed drive gear 120 is rotated, the upper
rotating shaft S1 (placed to the right when viewing the drawing),
to which the high-speed drive gear 120 is locked by the key K, is
rotated together. As well, the first main gear 121 is rotated at
the same speed as that of the rotating shaft S1.
[0099] As shown in FIG. 6, because the second main gear 122 engages
with the first main gear 121 which is locked to the rotating shaft
S1 by the key K, the first main gear 121 and the second main gear
122 are rotated in substantially opposite directions at
substantially the same angular speed.
[0100] In addition, because the second main gear 122 is locked to
the rotating shaft S2 by the key K, the rotating shaft S2 is also
rotated at substantially the same angular speed as that of the
second main gear 122.
[0101] As a result, the rotor units 200, which are respectively
coupled toward the ends of the rotating shafts S1 and S2 and form a
single or multiple structure, are rotated by the rotation of the
rotating shaft S2, thus executing the pumping operation.
[0102] A third embodiment of the clutch unit 100 of the present
invention will be explained herein below with reference to FIG.
7.
[0103] In the third embodiment of the clutch unit 100 coupled to
the overload prevention unit 20, a first gear 131, which engages
with the helical motor gear 12 that is eccentrically positioned, is
rotatably fitted over the rotating shaft S2, which is placed at a
position opposite the direction in which the helical motor gear 12
is offset. A first subsidiary gear 132, having a diameter smaller
than that of the first gear 131, is integrally provided beneath the
first gear 131. A second gear 133, which has a relatively large
diameter and engages with the first subsidiary gear 132, is
rotatably fitted over the other rotating shaft S1. A second
subsidiary gear 134, having a diameter smaller than that of the
second gear 133, is integrally provided beneath the second gear
133. Furthermore, a third gear 135, which has a relatively large
diameter and engages with the second subsidiary gear 134, is
rotatably fitted over the rotating shaft S2. A third subsidiary
gear 136, having a diameter smaller than that of the third gear
135, is integrally provided beneath the third gear 135. A fourth
gear 137, which has a relatively large diameter and engages with
the third subsidiary gear 136, is rotatably fitted over the other
rotating shaft S1. A fourth subsidiary gear 138, having a diameter
smaller than that of the fourth gear 137, is integrally provided
beneath the fourth gear 137. As well, a fifth gear 139, which has a
relatively large diameter and engages with the fourth subsidiary
gear 138, is rotatably fitted over the rotating shaft S2. A fifth
subsidiary gear 140, having a diameter smaller than that of the
fifth gear 139, is integrally provided beneath the fifth gear 139.
A drive gear 144, which has a relatively large diameter and engages
with the fifth subsidiary gear 140, is fitted over the other
rotating shaft S1 and locked to the other rotating shaft S1 by a
key K.
[0104] Furthermore, first and second main gears 145 and 146, having
substantially the same diameter, are respectively fitted over and
locked to the other rotating shaft S1 and the rotary shaft S2 using
keys K.
[0105] When the first, second, third, fourth and fifth gears 131,
133, 135, 137 and 139 and the first, second, third, fourth and
fifth subsidiary gears 132, 134, 136, 138 and 140 are fitted over
the first and second shafts S1 and S2, as discussed above, bearings
B are interposed between them such that the gears are smoothly
rotated at low speeds with respect to the rotating shafts S1 and
S2. The first and second main gears 145 and 146 are rotated at low
speeds by the rotational force transmitted through the drive gear
144, thus rotating the rotor units 200 at low speeds.
[0106] The operation of the third embodiment of the clutch unit 100
of the present invention will be explained herein below with
reference to FIG. 7.
[0107] When the helical motor gear 12, which is offset to one side,
is rotated, the first gear 131 having a relatively large diameter
is rotated.
[0108] At this time, the rotational speed of the drive motor 10
decreases.
[0109] Here, the first subsidiary gear 132 is integrally provided
beneath the first gear 131. The first subsidiary gear 132 has a
diameter smaller than the diameter of the first gear 131.
[0110] Of course, because the first gear 131 and the first
subsidiary gear 132 are integrated with each other, revolutions of
them are equal to each other.
[0111] The first subsidiary gear 132 engages with the second gear
133 fitted over the upper rotating shaft S1 (located on the right
side when viewing the drawing).
[0112] The first subsidiary gear 132 has a relatively small
diameter, and the diameter of the second gear 133 is larger than
that of the first subsidiary gear 132. Hence, when the rotational
force is transmitted from the first subsidiary gear 132 to the
second gear 133, the number of revolutions decreases.
[0113] Furthermore, the second subsidiary gear 134 is integrally
provided beneath the second gear 133.
[0114] As such, the gears are integrated with each other, so that
revolutions thereof are equal to each other.
[0115] The second subsidiary gear 134 engages with the third gear
135 fitted over the rotating shaft S2. Here, the third gear 135 has
the diameter larger than that of the second subsidiary gear 134, so
that the rotational speed is reduced when the rotational force is
transmitted.
[0116] The third subsidiary gear 136, having the diameter smaller
than that of the third gear 135, is integrally provided beneath the
third gear 135.
[0117] As such, because the third gear 135 and the third subsidiary
gear 136 are integrated with each other, revolutions thereof are
equal to each other. The above-mentioned gear coupling structure is
also applied throughout the fourth gear 137, the fourth subsidiary
gear 138, the fifth gear 139 and the fifth subsidiary gear 140, so
that the rotational speed is sequentially reduced. Furthermore, as
shown in FIG. 7, the fifth subsidiary gear 140 engages with the
drive gear 144 having a relatively large diameter. The drive gear
144 is locked to the upper rotating shaft S1.
[0118] Therefore, the upper rotating shaft S1 is rotated by the
rotation of the drive gear 144. Meanwhile, because bearings B are
provided around the rotating shafts S1 and S2 in the first, second,
third, fourth and fifth gears 131, 133, 135, 137 and 139 and the
first, second, third, fourth and fifth subsidiary gears 132, 134,
136, 138 and 140, they are smoothly rotated with respect to the
rotating shaft to execute the functions of the speed reduction.
[0119] In other words, the rotating shaft S1 is rotated only by
rotation of the drive gear 144. By this rotation, the first main
gear 145, which is located on the right (when viewing the drawing),
is rotated.
[0120] Of course, the number of revolutions of the first main gear
145 is equal to those of the drive gear 144 and the upper rotating
shaft S1. Furthermore, the first main gear 145 engages with the
second main gear 146. Hence, the second main gear 146 is rotated by
the rotation of the first main gear 145 in a direction opposite
that of the first main gear 145.
[0121] Furthermore, the second main gear 146 is locked to the lower
rotating shaft S1 by a key K, so that the lower rotating shaft S2
is also rotated at the same rotational speed as that of the second
main gear 146. As a result, the rotor units 200, which are coupled
to the rotating shafts S1 and S2, are rotated by the rotation of
the rotating shafts S1 and S2, thus executing the fluid pumping
operation. In the clutch unit 100 according to another embodiment
of the present invention, to further reduce the rotational speed
while the rotational force is transmitted, sixth through eleventh
gears and subsidiary gears (not shown) may be additionally provided
beneath the fifth gear 139 and the fifth subsidiary gear 140. That
is, other gears may be provided in the clutch unit 100 in the same
manner as the above-mentioned gear coupling structure. Then, the
rotational speed can be further reduced while the rotational force
is transmitted.
[0122] Using the above-mentioned principle, in yet another
embodiment, the clutch unit 100 may be a structure in which the
number of gears is less than the above embodiment, so as to reduce
the degree of speed reduction.
[0123] Of course, the clutch unit 100 having this structure falls
within the scope of the present invention. A fourth embodiment of
the clutch unit 100 of the present invention is shown in FIG.
8.
[0124] A construction of this embodiment is as follows. According
to this embodiment, in the clutch unit 100 coupled to the overload
prevention unit 20, a first gear 150, which engages with the
helical motor gear 12 that is eccentrically positioned, is
rotatably fitted over the rotating shaft S2, which is located at a
position opposite the direction in which the helical motor gear 12
is offset. A first subsidiary gear 151, having a diameter larger
than that of the first gear 150, is integrally provided beneath the
first gear 150. A second gear 152, which has a relatively small
diameter and engages with the first subsidiary gear 151, is
rotatably fitted over the other rotating shaft S1. A second
subsidiary gear 153, having a diameter larger than that of the
second gear 152, is integrally provided beneath the second gear
152.
[0125] Furthermore, a third gear 154, which has a relatively small
diameter and engages with the second subsidiary gear 153, is
rotatably fitted over the rotating shaft S2. A third subsidiary
gear 155, having a diameter larger than that of the third gear 154,
is integrally provided beneath the third gear 154. A fourth gear
156, which has a relatively small diameter and engages with the
third subsidiary gear 155, is rotatably fitted over the other
rotating shaft S1. A fourth subsidiary gear 157, having a diameter
larger than that of the fourth gear 156, is integrally provided
beneath the fourth gear 156.
[0126] Furthermore, a drive gear 158, which has a relatively small
diameter and engages with the fourth subsidiary gear 157, is fitted
over and locked to the rotating shaft S2 by a key K. First and
second main gears 160 and 161, having the same diameter, are
respectively fitted over and locked to the rotating shafts S2 and
S1 using keys K.
[0127] When the first, second, third and fourth gears 150, 152, 154
and 156 and the first, second, third and fourth subsidiary gears
151, 153, 155 and 157 are fitted over the first and second shafts
S1 and S2, bearings B are interposed between them such that the
gears are smoothly rotated at high speeds with respect to the
rotating shafts S1 and S2. The first and second main gears 160 and
161 are rotated at high speeds by the rotational force transmitted
through the drive gear 158, thus rotating the rotor units 200 at
high speeds.
[0128] An operation of the fourth embodiment of the clutch unit 100
will be explained herein below with reference to FIG. 8. When the
helical motor gear 12 fastened to the shaft 11 is rotated, the
first gear 150, which engages with the helical motor gear 12, is
rotated.
[0129] Here, the first gear 150 is rotatably fitted over the lower
rotating shaft S2 (located on the left when viewing the drawing),
and the first subsidiary gear 151, having a diameter larger than
that of the first gear 150, is integrally provided beneath the
first gear 150.
[0130] Therefore, when the first gear 150 is rotated, the first
subsidiary gear 151 is rotated along with the first gear 150. The
revolutions thereof are equal to each other. Simultaneously, the
second gear 152, which is fitted over the upper rotating shaft S1
(located on the right when viewing the drawing), is rotated by the
rotation of the first subsidiary gear 151.
[0131] At this time, when a relatively small gear is rotated by a
large gear, rotational speed of the small gear is increased
compared to that of the large gear, so that an increase in speed
between them is realized while power is transmitted.
[0132] Therefore, in this embodiment, when power is transmitted
from the first subsidiary gear 151 to the second gear 152, the
rotational speed is increased.
[0133] Furthermore, because the second subsidiary gear 153, having
a relatively large diameter, is integrated with the second gear
152, the number of revolutions of the second subsidiary gear 153 is
equal to the number of revolutions of the second gear 152.
[0134] When the second subsidiary gear 153 is rotated, the third
gear 154, which engages with the second subsidiary gear 153, is
simultaneously rotated.
[0135] Because this is a condition in which a gear having a large
diameter rotates a gear having a small diameter, the rotational
speed is further increased when the power is transmitted between
them.
[0136] As well, the third gear 154 is rotatably fitted over the
lower rotating shaft S2. The third subsidiary gear 155 having a
large diameter is integrated with the third gear 154, so that their
revolutions are equal to each other. The fourth gear 156, which is
rotatably fitted over the upper rotating shaft S1, engages with the
third subsidiary gear 155.
[0137] Because the third subsidiary gear 155 has a large diameter
and the fourth gear 156 has a small diameter, the rotational speed
is increased when the power is transmitted between them.
[0138] Furthermore, the fourth subsidiary gear 157, having a large
diameter, is integrated with the fourth gear 156, so that the
fourth gear 156 and the fourth subsidiary gear 157 are rotated at
the same angular speed.
[0139] The fourth subsidiary gear 157 engages with the drive gear
158 which has a small diameter and is locked to the lower rotating
shaft S2 by the key. Therefore, the power is transmitted from the
fourth subsidiary gear 157 having a large diameter to the drive
gear 158 having a small diameter, so that the rotational speed is
changed to high speed. Because the drive gear 158 is locked to the
lower rotating shaft S2 (placed at the lower position when viewing
the related drawing) by the key K, the rotating shaft S2 is rotated
along with the drive gear 158.
[0140] Furthermore, as shown in FIG. 8, the second main gear 161,
which is coaxial with the drive gear 158, is locked to the rotating
shaft S2 by the key K, so that they are rotated at the same angular
speed. The first main gear 160 engages with the second main gear
161, and the first and second main gears 160 and 161 have the same
diameter.
[0141] Therefore, the first main gear 160 is rotated by rotation of
the second main gear 161. At this time, they are rotated in
directions opposite each other. Furthermore, because the first main
gear 160 is locked to the upper rotating shaft S1 by the key K, the
rotating shaft S1 is rotated by the rotation of the first main gear
160. As a result, the rotational speed of the rotating shaft S1 is
changed to high speed by the clutch unit 100 of the fourth
embodiment. The rotating shaft S2 rotates the rotor units 200 of
the lower ends of the rotating shafts S1 and S2 in the state of
being rotated at a high speed. As described above, the first,
second, third and fourth gears 150, 152, 154 and 156 and the first,
second, third and fourth subsidiary gears 151, 153, 155 and 157 are
rotatably coupled to the rotating shafts S1 and S2 through the
bearings B, thus executing only the function of a change of
speed.
[0142] According to another embodiment, fifth through tenth gears
and subsidiary gears may (not shown) be additionally provided below
the fourth gear 156 and the fourth subsidiary gear 157 of FIG. 8 to
further increase the rotational speed of the rotating shafts.
[0143] The clutch unit 100 of the present invention has been
explained. Hereinafter, the rotor units 200, which are rotated by
rotation of the rotating shafts S1 and S2 changed in speed by the
clutch 100 and thus execute a function of pumping fluid, will be
described in detail. A first embodiment of the rotor unit 200 is
shown in FIGS. 9 through 12. A second embodiment of the rotor unit
200 is shown in FIGS. 15 and 16. First, the rotor unit 200
according to the first embodiment will be explained herein
below.
[0144] According to one embodiment as shown in FIGS. 9 and 10, each
rotor unit 200 of the present invention includes a cylindrical
housing 230 which has a cylindrical shape with a diameter smaller
than an inner diameter of the chamber 30. A plurality of bearing
seats 231 (FIG. 12) is formed in a circumferential inner surface of
the cylindrical housing 230. A space 235 is defined in the
cylindrical housing 230. Each rotor unit 200 further includes an
eccentric rotary body 220 which has a diameter smaller than the
inner diameter of the cylindrical housing 230 and is eccentrically
fifted over the rotating shaft S1 or S2, respectively.
[0145] Furthermore, a bearing means 210 is seated into each bearing
seat 231 of the cylindrical housing 230. Both the cylindrical
housing 230 and the eccentric rotary body 220 are provided in each
of the upper and lower chambers 30. The two cylindrical housings
230 are coupled to each other through a cross-plate 207 and are
eccentrically rotated.
[0146] As such, each of the rotor units 200 comprises the
cylindrical housing 230, the eccentric rotary body 220 and the
bearing means 210 provided in the cylindrical housing 230, such
that the two rotor units 200 are placed in the respective chambers
30.
[0147] The rotor units 200 are placed in the chambers 30 which
communicate with an inlet BC and an outlet BD are formed. Each
chamber 30 may include a substantially genuine circular
cross-section. Each of the rotor units 200 has the plurality of
bearing seats 231.
[0148] Needle roller bearings or ball bearings are seated into the
bearing seats 231 such that the rotor unit 200 is smoothly
eccentrically rotated.
[0149] Hereinafter, an operation of the rotor unit 200 will be
explained in detail.
[0150] As shown in FIGS. 9 through 12, the eccentric rotary bodies
220 of the rotor units 200 are fitted over the respective rotating
shafts S1 and S2, which can be coupled to the clutch unit 100
according to any of the embodiments described above.
[0151] At this time, each eccentric rotary body 220 is
eccentrically fitted over the corresponding rotating shaft S1, S2
but not coaxially fitted over it.
[0152] Therefore, when the rotating shafts S1 and S2 are rotated,
the eccentric rotary bodies 220 are eccentrically rotated.
[0153] The eccentric rotary bodies 220 move along the
circumferential inner surfaces of the chambers 30 in order to draw
and discharge fluid into and from the pump.
[0154] As shown in the drawings, when the eccentric rotary body
220, which is disposed at an upper position, is rotated in a
clockwise direction, the lower eccentric rotary body 220 is rotated
in a counterclockwise direction. Each rotating shaft S1, S2 is
coaxially provided in each chamber 30, and each eccentric rotary
body 220 is eccentrically fitted over each rotating shaft S1,
S2.
[0155] Therefore, when the eccentric rotary body 220 is rotated, a
moving track of a portion of the eccentric rotary body 220 which is
farthest from the rotating shaft is configured in a predetermined
shape. That is, the moving track is formed along the
circumferential inner surface of the chamber 30.
[0156] To ensure smooth movement of the eccentric rotary body 220,
the needle roller bearings or ball bearings are seated into the
bearing seats 231 formed in the circumferential inner surface of
the cylindrical housing 230.
[0157] Therefore, the circumferential outer surface of the
eccentric rotary body 220 is in rolling contact with the needle
roller bearings or ball bearings, while the eccentric rotary body
220 is rotated. Meanwhile, the eccentric rotary body 220 is
provided in each of the upper and lower rotor units 200. When the
upper rotating shaft S1 is rotated in a clockwise direction, the
eccentric rotary body 220 fitted over the upper rotating shaft S1
is also rotated in a clockwise direction, as shown in FIGS. 9 and
10.
[0158] In detail, in a state in which the upper rotor unit 200
contacts the uppermost portion of the circumferential inner surface
of the upper chamber 30 and the rotor units 200 are placed at a
vertical line, as shown in FIG. 9, if the rotating shaft S1 is
rotated in a clockwise direction, the associated eccentric rotary
body 220 is also rotated in a clockwise direction. At this time,
the bearing means (ball bearings or needle roller bearings) ensures
smooth rotation.
[0159] Rotation of the rotor units 200 will be described in detail
herein below. Referring to FIG. 9, in a state in which the rotor
units 200 are placed upright in the chambers, when the upper
eccentric rotary body 220 is rotated in a clockwise direction at
90.degree., a contact surface of the upper rotor unit 200 moves to
a portion of the inner surface of the upper chamber 30 which is
substantially in a 3 o'clock direction, that is, the portion
angularly spaced apart from the uppermost point at substantially
90.degree.. Simultaneously, the lower eccentric rotary body 220 is
rotated in a counterclockwise direction, so that a contact surface
of the lower rotor unit 200 moves to a portion of the inner surface
of the lower chamber 30 which is substantially in a 9 o'clock
direction, that is, the portion angularly spaced apart from the
uppermost point at substantially 270.degree.. When the upper
eccentric rotary body 220 is further rotated from the state shown
in the second view of FIG. 9 in a clockwise direction, the contact
surface of the upper rotary unit 200 moves to a lowermost portion
of the upper chamber 30 which is substantially in a 6 o'clock
direction, that is, the portion angularly spaced apart from the
uppermost point at substantially 180.degree.. Simultaneously, the
lower eccentric rotary body 220 is also further rotated in a
counterclockwise direction, so that the contact surface of the
lower rotary unit 200 moves to a portion of the inner surface of
the lower chamber 30 which is substantially in a 6 o'clock
direction, that is, the portion angularly spaced apart from the
uppermost point at substantially 180.degree. (see, the first view
of FIG. 10).
[0160] Subsequently, when the upper eccentric rotary body 220 is
further rotated from the state shown in the first view of FIG. 10
in a clockwise direction, the contact surface of the upper rotary
unit 200 moves to the lowermost portion of the upper chamber 30
which is substantially in a 9 o'clock direction, that is, the
portion angularly spaced apart from the uppermost point at
substantially 270.degree.. Simultaneously, the lower eccentric
rotary body 220 is also further rotated in a counterclockwise
direction, so that the contact surface of the lower rotary unit 200
moves to a portion of the inner surface of the lower chamber 30
which is substantially in a 3 o'clock direction, that is, the
portion angularly spaced apart from the uppermost point at
substantially 90.degree.. Thereafter, the process is returned to
the first step. As such, the process is continuously repeated, so
that fluid is pumped by movement of the rotor units 200.
[0161] When the rotor units 200 are placed at positions shown in
the first view of FIG. 9, the distance between the contact point
between the upper eccentric rotary body 220 and the upper
cylindrical housing 230 and the contact point between the lower
eccentric rotary body 220 and the lower cylindrical housing 230 is
shortest, as described above with reference to FIG. 4.
[0162] In other words, this means that the distance between the
contact points between the eccentric rotary bodies 220 and the
cylindrical housings 230 of the upper and lower rotor units 200 is
shortest. Of course, the distance between the rotating shafts S1
and S2, over which the eccentric rotary bodies 220 are fitted, are
constant without being varied.
[0163] When the rotor units 200 are placed at positions shown in
the second view of FIG. 9 by rotation of the rotating shafts S1 and
S2, the distance between the contact points between the eccentric
rotary bodies 220 and the cylindrical housings 230 becomes longest,
as described above with reference to FIG. 4.
[0164] In other words, the contact points between the eccentric
rotary bodies 220 and the cylindrical housings 230 of the upper and
lower rotor units 200 are farthest away from each other.
[0165] However, the positions of the rotating shafts S1 and S2
cannot be still changed.
[0166] Here, it is an important issue how to compensate for the
distance difference. To achieve the above-mentioned purpose,
embodiments of the present invention is designed such that the
diameter of each eccentric rotary body 220 is smaller than the
inner diameter of each cylindrical housing 230.
[0167] Therefore, as shown in the drawings, the space 235 is
defined between them such that the eccentric rotary body 220 is
movable in the space 235.
[0168] Thus, the distance difference is compensated for by the
space 235 while each eccentric rotary body is rotated in the space
235 of each cylindrical housing 230. Furthermore, in one embodiment
as shown in FIGS. 11 and 12, to ensure smoother movement of the
eccentric rotary bodies 220 in the cylindrical housings 230, the
bearing seats 231 are formed in the inner surface of the
cylindrical housings 230, and it is constructed such that the
bearing seats 231 have different depths.
[0169] That is, the bearing seats 231 are symmetrically formed
along the inner surface of the cylindrical housing 230 and have
different depths which are deeper in the order of
Gxa<G3a<G2a<Gla<Gya.
[0170] In detail, as shown in FIG. 12, the bearing seat Gya, which
is formed at the uppermost position of the cylindrical housing 230,
is deepest. The bearing seat G1a, which is formed at a position
spaced apart from the uppermost position at a predetermined angular
interval, is shallower than the bearing seat Gya. The depths of the
remaining bearings are shallower in the order of
G2a>G3a>Gxa.
[0171] Thus, when the ball bearings or needle roller bearings are
inserted into the bearing seats 231, as shown in FIG. 11, the ball
bearing or needle roller bearing seated into the bearing seat Gya
protrudes at the lowest height, and the ball bearings or needle
roller bearings seated into the bearing seats Gxa protrude at the
highest height.
[0172] Therefore, a track, along which the eccentric rotary body
220 contacts the ball bearings or needle roller bearings protruding
from the inner surface of the cylindrical housing 230, has at an
upper portion thereof an at least partially elliptical shape and at
a lower portion thereof an at least partially circular shape having
a relatively small curvature, as shown in FIG. 13.
[0173] The effect of this construction will be easily appreciated
with reference to FIG. 13. That is, the rotor unit 200 moves while
the distance difference induced in the cross-plate 207 of the rotor
unit 200 is compensated for by the space 235 defined in the rotor
unit 200. When the eccentric rotary body 220 is placed at positions
corresponding to the bearing seats Gxa, in other words, when the
eccentric rotary body 220 is placed in between a 3 o'clock
direction and a 9 o'clock direction, the eccentric rotary body 220
contacts the ball bearings or needle roller bearings which protrude
to greater heights from the inner surface of the cylindrical
housing 230.
[0174] As shown in the second view of FIG. 13, when the eccentric
rotary body 220 is in a 6 o'clock direction, because the ball
bearings or needle roller bearings, which are seated into the
bearing seats Gxa, protrude at greater heights, there is an
advantage in that the circumferential outer surface of the
cylindrical housing 230 can contact and seal a passage more
securely.
[0175] This effect provides more superior pumping performance.
[0176] As shown in FIG. 11, the bearing seats Gya, G1a, G2a, G3a
and Gxa are symmetrical with each other based on a Y-axis.
[0177] In detail, the bearing seats formed at an upper portion are
symmetrical based on the Y-axis, and the remaining bearing seats
Gxa formed at a lower portion have the same depth.
[0178] As such, the bearing seats are formed in shapes and to
depths shown in FIG. 11.
[0179] One of ordinary skill in the art will appreciate that the
above-mentioned effect may be realized both by bearing seats having
different diameter, and by ball bearings, which have the diameters
corresponding to the bearing seats and are seated into the bearing
seats.
[0180] That is, as shown in FIG. 14, the bearing seats 231 have
different diameters which are larger in the order of
Mya<M1a<M2a<M3a<Mxa. When sectioning the cylindrical
housing into upper and lower portions, the bearing seats Mxa formed
at the lower portion have the same diameter. Furthermore, each
bearing means, which is seated into each bearing seat, has the same
diameter as that of the associated bearing seat.
[0181] In other words, a height at which each bearing means, such
as ball bearings or needle roller bearing, protrudes from the
bearing seat is varied depending on the diameter of the bearing
means.
[0182] As such, when the ball bearings having diameters
corresponding to the respective bearing seats are seated into the
bearing seats, the diameters of which are larger in the order of
Mya<M1a<M2a<M3a<Mxa as the diameter of the bearing
seats is increased, the protruding height of a ball bearing seated
in the larger bearing seat is greater than the others.
[0183] In other words, the heights at which the ball bearings
protrude are higher in the same order as that of the bearing seats,
the diameters of which are larger in the order of
Mya<M1a<M2a<M3a<Mxa.
[0184] This structure also falls within the scope of the present
invention.
[0185] As described in brief above, in embodiments of the present
invention, various types of bearing means 210 may be seated into
the bearing seats 231.
[0186] For example, ball bearings or needle roller bearings may be
used as the bearing means 210.
[0187] If ball bearings are used as the bearing means, a plurality
of ball bearings is seated into each bearing seat 231. If needle
roller bearings, each having a predetermined length, are used as
the bearing means, a single needle roller bearing is seated into
each bearing seat 231.
[0188] It may be preferable that the ball bearings be used for
pumping fluid, such as water having a low viscosity, and the needle
roller bearings be used for pumping fluid, such as mud having a
high viscosity.
[0189] A second embodiment of the rotor unit 200 is shown in FIGS.
15 and 16. Hereinafter, the second embodiment will be explained in
detail with reference to these drawings. In the second embodiment
of the rotor unit 200, each rotor unit 200 includes a cylindrical
housing 230 which has a cylindrical shape with a diameter smaller
than an inner diameter of the chamber 30. A space 260 is defined in
the cylindrical housing 230. Each rotor unit 200 further includes
an eccentric rotary body 220 which has a diameter smaller than the
inner diameter of the cylindrical housing 230 and is eccentrically
fitted over the rotating shaft S1 or S2, respectively. A plurality
of bearing seats 271 is formed in a circumferential outer surface
of each eccentric rotary body 220.
[0190] Furthermore, a bearing means 210 is seated into each bearing
seat 271 of the eccentric rotary body 220.
[0191] Both the cylindrical housing 230 and the eccentric rotary
body 220 are provided in each of the upper and lower chambers 30.
The two cylindrical housings 230 are coupled to each other through
a cross-plate 207 and are eccentrically rotated.
[0192] As such, the general construction of the rotor unit 200
according to the second embodiment, except for the bearing seats
271 formed in the circumferential outer surface of the eccentric
rotary body 220, remains substantially the same as the rotor unit
200 according to the first embodiment.
[0193] The bearing means 210 is seated into each bearing seat 271
of the eccentric rotary bodies 220. The bearing means 210 serves to
provide a smoother rotation of each eccentric rotary body 220 in
each cylindrical housing 230.
[0194] Furthermore, the pumping operation of the rotor unit 200 of
the second embodiment is executed in substantially the same manner
as that of the first embodiment. Therefore, further explanation is
deemed unnecessary.
[0195] Meanwhile, in the second embodiment, the bearing seats 271
are symmetrically formed in the outer surface of the eccentric
rotary body 220 and have different depths, which are deeper in the
order of Fya<F3a<F2a<Fla<Fxa.
[0196] That is, unlike the first embodiment, the bearing seats 271
are formed along the circumferential outer surface of the eccentric
rotary body 220 and spaced apart from each other at regular angular
intervals. As shown in FIG. 16, of the bearing seats 271, the
bearing seats Fxa are deepest.
[0197] That is, the bearing seats Fxa, which are formed at
positions spaced apart from the uppermost point at substantially
90.degree., are deepest. The remaining bearing seats, which are
formed at positions spaced apart from each other at regular angular
intervals, are shallower in the order of
F1a>F2a>F3a>Fya.
[0198] In conclusion, the bearing seats Fxa are deepest, and the
bearing seats Fya are shallowest.
[0199] Furthermore, the two bearing seats 271, which are formed in
the outer surface of the eccentric rotary body 220 at symmetrical
positions based on the center of the eccentric rotary body 220 (at
positions spaced apart from each other at substantially
180.degree.), have the same depth. Therefore, when the bearing
means 210 is seated into each bearing seat 271, it is configured in
a shape shown in FIG. 15.
[0200] As shown in the drawing, the protruding height of the
bearing means (the ball bearings or the needle roller bearing),
which is seated into the bearing seat Fxa which is substantially in
a 3 o'clock direction, that is, formed in the eccentric rotary body
220 at a position spaced apart from the uppermost point at
substantially 90.degree., is lowest. The protruding height of the
bearing means 210 (the ball bearings or the needle roller bearing),
which is seated into the bearing seat Fya which is substantially in
a 12 o'clock direction, that is, formed in the eccentric rotary
body 220 at the uppermost position, is highest.
[0201] According to one embodiment, a modification of the second
embodiment is shown in FIG. 17. This modification, in which bearing
seats have different diameters and bearing means seated into the
bearing seats also have different diameters, has substantially the
same effect as that of the second embodiment. This modification is
as follows. The bearing seats 271, which are formed in each
eccentric rotary body, have diameters which are larger in the order
of Nxa<N1a<N2a<N3a<Nya. Each bearing means 210, which
is seated into each bearing seat 271, has the same diameter as that
of the associated bearing seat 271. Furthermore, the bearing seats
271 are symmetrically formed along the circumferential outer
surface of the eccentric rotary body 220.
[0202] Of course, as the diameters of the bearing seats 271 are
increased, the diameter of the bearing means 210 seated into the
bearing seats 271 becomes increased, so that the protruding height
of the bearing means 210 also becomes increased.
[0203] This modification has the same outline as that of the
above-mentioned embodiment and, thus, the effect thereof is also
substantially equal to the above-mentioned embodiment.
[0204] The outline of the eccentric rotary body 220 which is
defined by the bearing means 210 will be explained herein below. As
shown in FIG. 18, the outline of the eccentric rotary body 220,
which is defined by connecting the outermost points of the ball
bearings or needle roller bearings that protrude from the bearing
seats 271, is configured in an elliptical shape.
[0205] Here, the eccentric rotary body 220 having the elliptical
outline is eccentrically fitted over the rotating shaft, which is
rotated in place.
[0206] Therefore, as shown in FIG. 15 or 18, when the eccentric
rotary body 220 is rotated, the bearing means 210 (the ball
bearings or needle roller bearing), which is seated into the
uppermost bearing seat 271 having dimension Fya, mainly contacts
the inner surface of the cylindrical housing.
[0207] When the eccentric rotary body is rotated at substantially
90.degree. and thus enters the state of the second view of FIG. 18,
it is configured in an elliptical shape having a horizontal major
axis.
[0208] Subsequently, when the eccentric rotary body is rotated at
substantially 180.degree. and, thus, oriented in substantially a 6
o'clock direction, it compresses the portion of Fya having the
shallowest depth, as shown in the third view of FIG. 18.
[0209] Here, because the bearing seat 271 having dimension Fya has
the shallowest depth, the height at which the ball bearings or
needle roller bearing protrudes from the bearing seat 271 is
highest. Thereby, when the eccentric rotary body 220 is in the
above-mentioned state, the eccentric rotary body 220 most securely
pushes downwards the cylindrical housing 230.
[0210] Therefore, in the state shown in the last view of FIG. 18,
the eccentric rotary body 220 serves to reliably close the passage
formed below it, thus maximizing the pumping performance of the
pump.
[0211] Meanwhile, ball bearings or needle roller bearings can be
used as the bearing means 210 according to the second embodiment,
in substantially the same manner as that of the first embodiment.
Furthermore, it is preferred that angular intervals, at which the
ball bearings or needle roller bearings are spaced apart from each
other, are determined depending on a difference between the
diameter of the space 235 of the cylindrical housing 230 and the
outer diameter of the outline of the eccentric rotary body 220. To
easily illustrate this concept, FIG. 19 shows the elements with an
exaggerated size difference between them. As shown in the drawing,
if the diameter of the eccentric rotary body 220 is very small
compared to the space 235 defined in the cylindrical housing 230,
when the eccentric rotary body 220 is rotated along the inner
surface of the cylindrical housing 230 from the state in which the
uppermost ball bearing or needle roller bearing P contacts the
inner surface of the cylindrical housing 230, a subsequent contact
point becomes the point T. In other words, the contact points P and
T are very close.
[0212] Here, as the diameter of the eccentric rotary body 220
becomes smaller, the distance between the contact points is
reduced. Conversely, as shown in FIG. 20, if the diameter of the
eccentric rotary body 220 is large to the degree similar to the
size of the space 235 of the cylindrical housing 230, when the
eccentric rotary body 220 is rotated along the inner surface of the
cylindrical housing 230 from the state in which the uppermost ball
bearing or needle roller bearing P contacts the inner surface of
the cylindrical housing 230, a subsequent contact point becomes the
point T of FIG. 20.
[0213] As such, the distance between the adjacent contact points P
and T is increased compared to the case of FIG. 19.
[0214] Accordingly, as the diameter of the eccentric rotary body
220 is reduced, the number of required ball bearings or needle
roller bearings is increased. As the diameter of the eccentric
rotary body 220 is increased, the number of required ball bearings
or needle roller bearings is reduced.
[0215] FIGS. 21 through 29 illustrate various embodiments
incorporating distinct structures for the chamber 30. For example,
one through ten pairs of upper and lower chambers 30, each having
the rotor unit 200 therein, may be constructed in a row to form a
multiple structure.
[0216] The term `multiple structure` means that several rotor units
200 and chambers 30 may be provided on each of the upper and lower
rotating shafts.
[0217] In detail, in the multiple rotary pump according to an
embodiment of the present invention, a plurality of chambers 30 is
disposed in a row. Separation plates are interposed between the
chambers 30, so that the chambers 30 are divided. The upper rotors
units 200 and the lower rotor units 200, which are provided in the
chambers 30, are respectively fitted over the single upper rotating
shaft S1 and the single lower rotating shaft S2, respectively. The
upper rotors units 200 and the lower rotor units 200, which are
respectively fitted over the upper and lower rotating shafts S1 and
S2 and are provided in the chambers 30, are arranged such that they
differ in phase. The upper and lower rotating shafts S1 and S2
receive power from the drive motor through the clutch unit. Each of
the upper and lower rotor units 200 may have a structure of the
rotor unit 200 as described above according to the first or second
embodiment.
[0218] In an embodiment of the multiple rotary pump of the present
invention, as described above, because no torsional stress is
applied to the upper rotating shaft S1 and the lower rotating shaft
S2, even when the upper and lower rotor units 200, which are
respectively provided on the upper and lower rotating shafts S1 and
S2 and have different phases, are rotated, they are not damaged.
Furthermore, even if the upper and lower rotating shafts S1 and S2
are rotated at high speeds, because they are stable, the upper and
lower rotor units 200 can be stably rotated at high speeds.
[0219] Furthermore, referring to FIGS. 21 through 29, in the
multiple rotary pump having the above-mentioned construction and
operation, manifolds may be coupled to inlets BC and outlets BD of
the chambers 30. In this case, a mixture ratio of two or more kinds
of fluid, which is drawn into the chambers 30 and discharged from
the chambers 30, can be controlled.
[0220] For example, as shown in FIG. 25, a first manifold CQ is
coupled to inlets BC of first, second and third chambers CA, CB and
CC, and a separate inlet pipe CF is coupled to an inlet BC of a
fourth chamber CD.
[0221] Then, objective fluid is drawn into the first, second and
third chambers CA, CB and CC through the first manifold, while
diluent (water or chemical) is drawn into the fourth chamber CD
through the inlet pipe. Both the objective fluid and the diluent
are discharged from the chambers 30 through a second manifold CT
coupled to the outlets of the chambers 30. Therefore, a mixture
ratio of diluent to objective fluid to be discharged through the
second manifold CT can be constantly controlled.
[0222] According to another embodiment as shown in FIG. 26, a
multiple rotary pump may be constructed such that a third manifold
DA is coupled to the inlets of the first and second chambers CA and
CB and a fourth manifold DB is coupled to the inlets of the third
and fourth chambers CC and CD.
[0223] In FIG. 26, the reference character CT denotes a second
manifold coupled to the outlets of the chambers.
[0224] Furthermore, in other embodiments, as shown in FIG. 27 or
28, the multiple rotary pump may be constructed such that a fifth
manifold FA is coupled to the outlets BD of the first, second and
third chambers CA, CB and CC and a separate outlet pipe FB is
coupled to the outlet of the fourth chamber CD or, alternatively, a
sixth manifold GA is coupled to the outlets BD of the first and
second chambers and a seventh manifold GB is coupled to the outlets
BD of the third and fourth chambers CC and CD.
[0225] Thereby, objective fluid discharged from the first, second,
third and fourth chambers CA, CB, CC and CD can be divided in a
desired ratio.
[0226] According to one embodiment, the overload prevention unit 20
is provided between the output shaft 11 of the drive motor 10 and
the clutch shaft, as shown in FIGS. 4, 5, 6, 30 and 31.
[0227] In one embodiment, the overload prevention unit 20 comprises
a plurality of ball seats 21, which are formed in a circumferential
outer surface of an end of the output shaft of the drive motor 10,
and a coupler 24 which is coupled to the clutch unit 100, with a
receiving space 22 defined in the coupler 24. The output shaft 11
is inserted into the receiving space 22. A plurality of ball
insertion holes 23 are formed along a sidewall of the coupler 24 at
positions corresponding to the ball seats 21.
[0228] Furthermore, a cover ring 26, which is made of synthetic
resin, is fitted over a circumferential outer surface of the
coupler 24 to prevent balls 25 (FIG. 31) from being undesirably
removed.
[0229] Therefore, each ball 25 is inserted into each ball insertion
hole 23 and seated into each ball seat 21. The balls 25 are covered
with the cover ring 26. When an overload is applied to the clutch
unit 100, the balls 25 are removed from the ball seats 21 while
pushing outwards the cover ring 26, thus preventing power from
being transmitted.
[0230] The end of the output shaft 11 of the drive motor 10 is
tapered, and the ball seats 21 are formed in the circumferential
outer surface of the end of the output shaft 11.
[0231] The helical motor gear 12 is provided on an end of the
coupler 24, which has the receiving space 22 into which the end of
the output shaft 11 of the drive motor 10 is inserted. The ball
insertion holes 23, which are formed the sidewall of the coupler at
positions corresponding to the ball seats 21, communicate with the
receiving space 22.
[0232] Therefore, when the coupler 24 is coupled to the output
shaft of the drive motor 10 after the balls are inserted into the
ball insertion holes 23, the balls 25 are seated into the ball
seats 21.
[0233] Furthermore, because the cover ring 26 is fitted over the
coupler 24, the balls 25 are stopped by the inner surface of the
cover ring 26, thus being prevented from being undesirably removed
from the coupler 24, and maintaining the state of being reliably
seated into the ball seats 21. Therefore, the coupler 24 reliably
couples the drive motor 10 to the clutch unit 100 such that, when
the drive motor 10 is rotated, power is securely transmitted.
[0234] However, if an overload is applied to the drive motor 10 due
to rubble or a foreign substance having high hardness being trapped
in the rotor unit 200 or the clutch unit 100, the coupler 24, which
couples the clutch unit 100 to the output shaft 11 of the drive
motor 10, can no longer rotate and must submit to the overload. At
this time, if the overload is increased, the balls 25 push the
cover ring 26 made of synthetic resin outwards and are thus removed
from the ball seats 21.
[0235] As such, embodiment of the present invention having the
overload prevention unit 20 can solve a problem of breakage in the
clutch unit 100, which has been frequently induced in the
conventional pumps.
[0236] That is, in the conventional pumps, in the above-mentioned
condition of an overload, there is a problem in that gear teeth of
the clutch unit 100 are damaged by an overload applied to the gear
teeth. However, the present invention can solve this problem using
the overload prevention unit 20.
[0237] The various embodiments described above can be combined to
provide further embodiments. All of the U.S. patents, U.S. patent
application publications, U.S. patent applications, foreign
patents, foreign patent applications and non-patent publications
referred to in this specification and/or listed in the Application
Data Sheet, are incorporated herein by reference, in their
entirety. Aspects of the embodiments can be modified, if necessary
to employ concepts of the various patents, applications and
publications to provide yet further embodiments.
[0238] These and other changes can be made to the embodiments in
light of the above-detailed description. In general, in the
following claims, the terms used should not be construed to limit
the claims to the specific embodiments disclosed in the
specification and the claims, but should be construed to include
all possible embodiments along with the full scope of equivalents
to which such claims are entitled. Accordingly, the claims are not
limited by the disclosure.
* * * * *