U.S. patent application number 13/616963 was filed with the patent office on 2013-04-04 for power generation apparatus.
This patent application is currently assigned to Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.). The applicant listed for this patent is SHIGETO ADACHI, MASAYOSHI MATSUMURA, YUTAKA NARUKAWA, KAZUO TAKAHASHI. Invention is credited to SHIGETO ADACHI, MASAYOSHI MATSUMURA, YUTAKA NARUKAWA, KAZUO TAKAHASHI.
Application Number | 20130084164 13/616963 |
Document ID | / |
Family ID | 46970059 |
Filed Date | 2013-04-04 |
United States Patent
Application |
20130084164 |
Kind Code |
A1 |
ADACHI; SHIGETO ; et
al. |
April 4, 2013 |
POWER GENERATION APPARATUS
Abstract
A power generation apparatus includes an expander and a power
transmission shaft that extracts a rotational driving force
generated by the expander to the exterior of a housing of the
expander. The housing of the expander contains a driving unit of
the expander within a space enclosed by a partition wall of the
housing. The power transmission shaft includes a magnetic coupling,
divided between the interior and exterior of the housing of the
expander through the partition wall. The rotational driving force
extracted via the magnetic coupling is used as auxiliary power that
supplements the power of a driving source provided separately from
the expander when driving a rotating machine using the power of the
driving source. A clutch mechanism and a speed variator are
provided in a power transmission path that transmits the rotational
driving force extracted by the power transmission shaft to the
driving source.
Inventors: |
ADACHI; SHIGETO;
(Takasago-shi, JP) ; MATSUMURA; MASAYOSHI;
(Takasago-shi, JP) ; NARUKAWA; YUTAKA;
(Takasago-shi, JP) ; TAKAHASHI; KAZUO;
(Takasago-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ADACHI; SHIGETO
MATSUMURA; MASAYOSHI
NARUKAWA; YUTAKA
TAKAHASHI; KAZUO |
Takasago-shi
Takasago-shi
Takasago-shi
Takasago-shi |
|
JP
JP
JP
JP |
|
|
Assignee: |
Kabushiki Kaisha Kobe Seiko Sho
(Kobe Steel, Ltd.)
Kobe-shi
JP
|
Family ID: |
46970059 |
Appl. No.: |
13/616963 |
Filed: |
September 14, 2012 |
Current U.S.
Class: |
415/122.1 |
Current CPC
Class: |
F01K 25/08 20130101 |
Class at
Publication: |
415/122.1 |
International
Class: |
F01D 15/12 20060101
F01D015/12 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 3, 2011 |
JP |
2011-219227 |
Claims
1. A power generation apparatus comprising: an expander; a housing
that houses the expander, the housing containing a driving unit of
the expander within a space enclosed by a partition wall of the
housing; a power transmission shaft that extracts rotational
driving force generated by the expander to the exterior of the
housing, the power transmission shaft including a magnetic
coupling, for transmitting the rotational driving force from the
expander to the exterior of the housing, that is divided between
the interior and exterior of the housing of the expander through
the partition wall; a driving source provided separately from the
expander, the rotational driving force extracted by the power
transmission shaft being used as auxiliary power for supplementing
the power of the driving source when driving a rotating machine
using the power of the driving source; a clutch mechanism, provided
in the power transmission path that transmits the rotational
driving force extracted by the power transmission shaft to the
driving source, that controls a transmission state of the
rotational driving force; and a speed variator, provided in the
power transmission path, that changes and transmits a rotational
speed of the power transmission shaft.
2. The power generation apparatus according to claim 1, wherein an
electricity generator that generates electricity using the
rotational driving force is provided in the power transmission
path.
3. The power generation apparatus according to claim 1, wherein an
electricity generator that generates electricity using the
rotational driving force extracted via the driving unit of the
expander and transmits power generated by the expander to the power
transmission shaft is provided within the housing.
4. A power generation apparatus that drives a compressor that
compresses a gas to a high pressure, the apparatus comprising: a
thermal engine, the thermal engine including an evaporator that
evaporates a liquid working medium using heat supplied from a heat
source, an expander that produces rotational driving force by
expanding the working fluid evaporated by the evaporator, a
condenser that converts the working fluid expanded by the expander
into a liquid working medium by condensing the working fluid, and a
medium circulation pump that pressure-transfers the liquid working
medium to the evaporator; a housing that houses the expander, the
housing containing a driving unit of the expander within a space
enclosed by a partition wall of the housing; a power transmission
shaft that extracts rotational driving force generated by the
expander to the exterior of the housing, the power transmission
shaft including a magnetic coupling, for transmitting the
rotational driving force from the expander to the exterior of the
housing, that is divided between the interior and exterior of the
housing of the expander through the partition wall; and a driving
source provided separately from the expander, the rotational
driving force extracted by the power transmission shaft being used
as auxiliary power for supplementing the power of the driving
source when driving the compressor using the power of the driving
source, wherein heat of the gas that has been adiabatically
compressed by the compressor is supplied to the evaporator as the
heat source for evaporating the liquid working medium.
5. The power generation apparatus according to claim 4, wherein the
power generation apparatus drives a multi-stage compressor that
includes two or more compressors; and the high-pressure gas
discharged from each compressor in the multi-stage compressor is
supplied to the evaporator as the heat source for evaporating the
working medium within the thermal engine.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to power generation
apparatuses that extract power generated by a thermal engine to the
exterior of the thermal engine and use that power as auxiliary
power that supplements the power of a driving source provided
separately from the thermal engine.
[0003] 2. Description of the Related Art
[0004] Among thermal engines, external combustion engines are
configured to convert heat into power (that is, convert heat energy
into kinetic energy) by expanding and condensing a working medium
(also called a working fluid), such as water or a low-boiling point
medium (that is, a medium having a lower boiling point than water)
such as ammonia, pentane, Freon, alternative Freon, or the like,
through a thermodynamic cycle such as a Rankine cycle. Such a
thermal engine includes an expander that expands working medium
vapor, and the expander is contained within a housing that is
separated from the exterior in an airtight state. Rotational
driving force obtained through this expander is extracted to the
exterior of the housing in which the expander is contained via a
shaft, and is used to rotate a rotating machine such as a
compressor, a blower, a pump, an electricity generator, or the
like.
[0005] For example, JP-2009-185772A discloses a fluid machine,
including an expanding mechanism that generates rotational force by
expanding a working fluid, an electricity generator driven by the
rotational force of the expanding mechanism, and a pump mechanism
driven by the rotational force of the expanding mechanism; the
fluid machine is configured so that the volume of the pump
mechanism is variable.
[0006] Meanwhile, JP-2005-30386A discloses a fluid machine
including an expander that converts heat energy from a Rankine
cycle into rotational power, a liquid supply pump that is driven by
the rotational power and increases the pressure in the Rankine
cycle, and a motor that generates rotational driving force; a
rotating shaft is shared by these elements.
[0007] These apparatuses (fluid machines) both contain an expander,
which is part of a thermal engine, and a rotating machine such as
an electricity generator or a pump together within a single
housing.
[0008] Incidentally, with the apparatuses (fluid machines)
disclosed in the aforementioned background art, it is absolutely
necessary to provide a seal in the housing that contains the
expander in order to prevent the working medium from leaking.
[0009] In the case where the expander and a rotating machine such
as an electricity generator or a pump are contained within a single
housing, as disclosed in JP-2009-185772A and the example in FIG. 1
of JP-2005-30386A, there are situations where a shaft seal for a
shaft that connects the expander and the rotating machine is not
needed. However, specialized components are required for the
housing or the rotating machine, which poses a problem in that
generic components cannot be used. This can also easily lead to an
increase in the initial costs of the power generation apparatus, or
electricity generation equipment that uses the power generation
apparatus.
[0010] On the other hand, in the case where a rotational shaft for
transmitting power passes through the housing and protrudes to the
exterior, as shown in FIGS. 19, 20, and so on of JP-2005-30386A, a
seal for the shaft is extremely important particularly in binary
electricity generation, in which a low-boiling point medium, which
should not be exposed to the atmosphere, is used as the working
medium. With this equipment, a structure is employed in which a
shaft seal is provided between a rotary machine (a motor 9) and an
expander, and thus the working medium does not leak toward the
rotary machine. However, it is difficult to prevent the working
medium from leaking with certainty even if this type of shaft seal
is employed, and it is also necessary to carry out complicated
maintenance procedures on the shaft seal. Further, this can easily
lead to an increase in the running costs of the power generation
apparatus, or electricity generation equipment that uses the power
generation apparatus.
[0011] Having been achieved in light of the stated problems, it is
an object of the present invention to provide a power generation
apparatus capable of efficiently transmitting rotational driving
force generated by an expander to the exterior of a housing that
contains the expander while preventing a working medium from
leaking, even without the thermal engine and a rotary machine being
contained together within a single housing, or without a shaft
sealing mechanism being employed on a shaft that transmits power,
and that transmits the rotational driving force to a rotating
machine driven by power from a driving source provided separately
from the thermal engine and uses the rotational driving force as
auxiliary power for supplementing the power from the driving
source.
SUMMARY OF THE INVENTION
[0012] In order to achieve the above object, a power generation
apparatus according to the present invention includes the following
technical means.
[0013] That is, a power generation apparatus according to the
present invention includes: an expander; a housing that houses the
expander, the housing containing a driving unit of the expander
within a space enclosed by a partition wall of the housing; a power
transmission shaft that extracts rotational driving force generated
by the expander to the exterior of the housing, the power
transmission shaft including a magnetic coupling, for transmitting
the rotational driving force from the expander to the exterior of
the housing, that is divided between the interior and exterior of
the housing of the expander through the partition wall; a driving
source provided separately from the expander, the rotational
driving force extracted by the power transmission shaft being used
as auxiliary power for supplementing the power of the driving
source when driving a rotating machine using the power of the
driving source; a clutch mechanism, provided in the power
transmission path that transmits the rotational driving force
extracted by the power transmission shaft to the driving source,
that controls a transmission state of the rotational driving force;
and a speed variator, provided in the power transmission path, that
changes and transmits a rotational speed of the power transmission
shaft.
[0014] In the above power generation apparatus, an electricity
generator that generates electricity using the rotational driving
force may be provided in the power transmission path.
[0015] In the above power generation apparatus, an electricity
generator that generates electricity using the rotational driving
force extracted via the driving unit of the expander and transmits
power generated by the expander to the power transmission shaft may
be provided within the housing.
[0016] In addition, a power generation apparatus according to the
present invention drives a compressor that compresses a gas to a
high pressure, and includes: a thermal engine, the thermal engine
including an evaporator that evaporates a liquid working medium
using heat supplied from a heat source, an expander that produces
rotational driving force by expanding the working fluid evaporated
by the evaporator, a condenser that converts the working fluid
expanded by the expander into a liquid working medium by condensing
the working fluid, and a medium circulation pump that
pressure-transfers the liquid working medium to the evaporator; a
housing that houses the expander, the housing containing a driving
unit of the expander within a space enclosed by a partition wall of
the housing; a power transmission shaft that extracts rotational
driving force generated by the expander to the exterior of the
housing, the power transmission shaft including a magnetic
coupling, for transmitting the rotational driving force from the
expander to the exterior of the housing, that is divided between
the interior and exterior of the housing of the expander through
the partition wall; and a driving source provided separately from
the expander, the rotational driving force extracted by the power
transmission shaft being used as auxiliary power for supplementing
the power of the driving source when driving the compressor using
the power of the driving source, in which heat of the gas that has
been adiabatically compressed by the compressor is supplied to the
evaporator as the heat source for evaporating the liquid working
medium.
[0017] The power generation apparatus may drive a multi-stage
compressor that includes two or more compressors, and the
high-pressure gas discharged from each compressor in the
multi-stage compressor may be supplied to the evaporator as the
heat source for evaporating the working medium within the thermal
engine.
[0018] According to the power generation apparatus of the present
invention, the rotational driving force generated by the expander
can be efficiently transmitted to the exterior of the housing that
contains the expander while preventing a working medium from
leaking, even without employing a shaft seal mechanism on the shaft
that transmits the power; in addition, the rotational driving force
can be transmitted to the rotating machine that is driven by the
power of the driving source provided separately from the expander
and used as auxiliary power for supplementing the power of the
driving source. It is also unnecessary to provide the expander and
the driving source together within a single housing. Furthermore,
because the clutch mechanism and the speed variator are provided,
the rotational driving force generated by the expander can be
applied to the driving source as auxiliary power at an appropriate
rotational frequency when it is necessary to add the auxiliary
power.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a diagram illustrating a power generation
apparatus according to a first embodiment.
[0020] FIG. 2 is a diagram illustrating a power generation
apparatus according to a second embodiment.
[0021] FIG. 3 is a diagram illustrating a power generation
apparatus according to a third embodiment.
[0022] FIG. 4 is a diagram illustrating a power generation
apparatus according to a fourth embodiment.
[0023] FIG. 5 is a diagram illustrating a power generation
apparatus according to a fifth embodiment.
[0024] FIG. 6 is a diagram illustrating a power generation
apparatus according to a sixth embodiment.
[0025] FIG. 7 is a diagram illustrating a power generation
apparatus according to a seventh embodiment.
[0026] FIGS. 8A and 8B are diagrams illustrating the transmission
of power from an expander to a motor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0027] Hereinafter, a first embodiment of a power generation
apparatus 1 according to the present invention will be described
based on the drawings.
[0028] As shown in FIG. 1, the power generation apparatus 1
according to the first embodiment includes: a thermal engine 4
provided with an expander 3 that has a driving unit 2 (a screw
rotor 2, in the present embodiment) rotationally driven by
expanding the vapor of a working fluid T; and a power transmission
shaft 6 that extracts rotational driving force generated by the
expander 3 to the exterior of a housing 5 that contains the
expander 3. The housing 5 contains the driving unit 2 of the
expander 3 within a space enclosed by a partition wall 7 of the
housing 5. The power transmission shaft 6 is divided by the
partition wall 7 into a drive shaft 8 located within the housing 5
and a slave shaft 9 located outside of the housing 5. A magnetic
coupling 10 is provided in the divided power transmission shaft 6,
or in other words, in the drive shaft 8 and the slave shaft 9, in
order to transmit the rotational driving force of the expander 3 to
the exterior of the housing 5. In this manner, the power generation
apparatus 1 is configured of the drive shaft 8 and the slave shaft
9, which make up the power transmission shaft 6, and the magnetic
coupling 10; the rotational driving force is transmitted to the
exterior of the housing 5 by the power transmission shaft 6. The
configuration is such that the rotational driving force transmitted
to the exterior is transmitted to a rotating machine 11 provided
separately from the thermal engine 4, and the rotational driving
force is used as auxiliary power for the rotating machine 11.
[0029] Note that in the first embodiment, a binary cycle is
illustrated as an example of the thermal engine 4. That said, any
engine may be included as the thermal engine 4 as long as it is an
engine that converts heat into power. Steam engines, steam
turbines, external combustion engines using a Stirling cycle, or
internal combustion engines such as gas turbines are also included
in addition to engines that use a Rankine cycle such as a binary
cycle.
[0030] As shown in FIG. 1, the binary cycle includes, in a cyclic
channel connected as a closed loop: an evaporator 13 that
evaporates the liquid working fluid T; the expander 3 that
rotationally drives the driving unit 2 (for example, the screw
rotor 2, which will be described later) by expanding the vapor of
the working fluid T evaporated by the evaporator 13; a condenser 12
that condenses the vapor of the working fluid T expanded by the
expander 3 and converts the working fluid T into liquid; and a
medium circulation pump 14 that circulates the working fluid T by
pressure-transferring the liquid working fluid T condensed by the
condenser 12 to the evaporator 13.
[0031] The expander 3 includes the screw rotor 2 (driving unit 2)
that is rotationally driven by a pressure difference between the
pre- and post-expansion vapor. The screw rotor 2 is capable of
freely rotating central to the drive shaft 8, and can transmit the
generated rotational driving force via the drive shaft 8 to the
magnetic coupling 10 connected to the drive shaft 8.
[0032] The housing 5 (partition wall 7) is provided around the
screw rotor (driving unit) 2 of the expander 3, and the interior
and exterior can be partitioned in an airtight state by the housing
5. The working fluid T, which is a low-boiling point medium used in
the binary cycle, is contained along with the screw rotor 2 within
the housing 5 that is partitioned in an airtight state in this
manner.
[0033] In the case where the rotational driving force produced by
the aforementioned screw rotor of the expander is to be transmitted
to a rotating machine driven by the power of a driving source
provided separately from the thermal engine in which the expander
is provided (that is, the aforementioned binary cycle or the like)
and used as auxiliary power for driving the rotating machine, it is
normally necessary to provide a power transmission means between
the expander and the rotating machine that can transmit the
rotational driving force generated by the expander to the rotating
machine.
[0034] Conventionally, in the case where a rotational shaft
provided so as to pass through the interior and exterior of the
expander housing is employed as the power transmission means, it is
absolutely necessary to provide a shaft seal that suppresses the
working fluid from leaking from between the rotational shaft and
the housing. Providing such a shaft seal is undesirable because it
complicates the maintenance of the apparatus, leads to an increase
in the running cost, and carries the risk of leaking of the working
fluid that is contained. In order to solve this problem, the
working fluid has conventionally been prevented from leaking by
containing the expander and the rotating machine together within a
single housing. Although there are cases where containing the
expander and the rotating machine together within a single housing
in this manner makes it unnecessary to provide a shaft seal between
the two, doing so also severely limits the range of items that can
be applied as the rotating machine, which is undesirable as it
leads to an increase in initial costs and makes it impossible to
use generic components.
[0035] Accordingly, the power generation apparatus 1 according to
the present invention includes the magnetic coupling 10 that
transmits the rotational driving force of the expander 3 to the
exterior of the housing 5 through the partition wall 7. In other
words, to enable rotational driving force to be transmitted between
the expander 3 and the rotating machine 11, the power generation
apparatus 1 includes a power transmission path 15 that has the
power transmission shaft 6, which is separated into the drive shaft
8 and the slave shaft 9 with the partition wall 7 therebetween, and
the magnetic coupling 10, which magnetically couples the two shafts
that are separated between the interior and exterior of the housing
5 with the partition wall 7 therebetween. The rotational driving
force extracted via the magnetic coupling 10 is transmitted to the
rotating machine 11 driven by the power of a driving source 16
provided separately from the aforementioned thermal engine 4
(binary cycle), and is used as auxiliary power for driving the
rotating machine 11.
[0036] Meanwhile, a speed variator 17 that changes the rotational
speed of the power transmission shaft 6 and transmits the auxiliary
power downstream, and a clutch mechanism 18 that controls the state
of transmission of the auxiliary power to the rotating machine 11,
are provided in the power transmission path 15, through which the
rotational driving force extracted via the magnetic coupling 10 is
transmitted.
[0037] Next, descriptions will be given of the magnetic coupling
10, power transmission shaft 6, speed variator 17, and clutch
mechanism 18 of which the power generation apparatus 1 is
configured, and of the rotating machine 11 that uses the auxiliary
power generated by the expander 3.
[0038] As shown in FIG. 1, the drive shaft 8, which is one part of
the power transmission shaft 6, is a rotational shaft disposed
following the center of the rotational axis of the screw rotor 2 in
the expander 3. One end of the drive shaft 8 (the left side in FIG.
1) is coupled with the screw rotor 2, which serves as the driving
unit 2 of the expander 3, and the other end (the right side in FIG.
2) extends to the vicinity of the partition wall 7; an outer
cylinder 20 of the magnetic coupling 10, in which driving-side
magnets are mounted, is provided on the leading end of this other
side.
[0039] Meanwhile, the slave shaft 9, which is a part of the power
transmission shaft 6, is a rotatable shaft disposed following the
direction that is coaxial with the drive shaft 8. One end of the
slave shaft 9 (the left side in FIG. 1) extends toward the expander
3, and an insertion member 22 to which slave-side magnets are
attached is provided on this one end; the other end (the right side
in FIG. 1) is connected to the rotating machine 11, which will be
mentioned later.
[0040] The magnetic coupling 10 is configured of the outer cylinder
20 provided on the drive shaft 8 and the insertion member 22
provided on the slave shaft 9. The outer cylinder 20 is a
closed-end cylindrical member that is open on the side that faces
the rotating machine 11 (the side opposite to the screw rotor 2),
and is formed of a nonmagnetic material. The drive shaft 8 is
coupled coaxially with the outer cylinder 20, and the two
driving-side magnets, which are disposed separated from each other
in the circumferential direction, are provided opposite to each
other in areas of the outer cylinder 20 formed in the cylindrical
shape.
[0041] The insertion member 22 is a circular column-shaped member,
and is, like the outer cylinder 20, formed of a nonmagnetic
material. The insertion member 22 can be inserted into the outer
cylinder 20 with a gap therebetween, and the slave-side magnets,
which are of a number based on the driving-side magnets, are
attached on the outer circumferential surface of the insertion
member 22 (the outer circumferential surface of the portion that is
inserted into the outer cylinder 20).
[0042] The driving-side magnets and the slave-side magnets are
disposed so that opposite poles are facing one another, so that
magnetic pull is induced between the magnets through the partition
wall 7; thus the rotational driving force of the drive shaft 8 can
be transmitted to the slave shaft 9.
[0043] Although the driving-side magnets and the slave-side magnets
are, in this example, permanent magnets such as neodymium magnets
or samarium-cobalt magnets, it should be noted that electro-magnets
may also be used.
[0044] The rotational driving force extracted to the exterior of
the housing 5 via the magnetic coupling 10 is transmitted to the
aforementioned slave shaft 9, and the rotational driving force can
be transmitted to the speed variator 17 via the slave shaft 9. The
speed variator 17 is an element that changes the rotational speed
on an input side (the slave shaft 9) to the optimal rotational
speed for the rotating machine 11 and transmits the rotational
driving force to an output side (the slave shaft 9). In addition, a
rotational shaft of the rotating machine 11 (a pump drive shaft 23,
which will be mentioned later) is connected to the slave shaft 9.
The rotational driving force whose speed has been changed by the
speed variator 17 in this manner is transmitted downstream as
auxiliary power for the rotating machine 11. A component that uses
gears, belts, or the like can be used as the speed variator 17.
Furthermore, a component that decreases, increases, or maintains
the rotational frequency between the input-side shaft and the
output-side shaft can be used as the speed variator 17.
[0045] The clutch mechanism 18 is a component that controls the
state of the transmission of the auxiliary power to the rotating
machine 11; the clutch mechanism 18 is provided on the output side
(the slave shaft 9) of the speed variator 17 in the power
transmission path 15, and can interrupt/resume the transmission of
the rotational driving force to the rotating machine 11. The clutch
mechanism 18 includes a pair of clutch plates (not shown) disposed
so as to face each other and an operation lever 24 operated so as
to engage/disengage the pair of clutch plates. By using the
operation lever 24 to bring the surfaces of the clutch plates into
contact with each other or separate from each other, the
transmission of the rotational driving force to the rotating
machine 11 can be interrupted. Note that a friction clutch, which
produces a given state of slippage when controlling the state of
transmission, can be favorably used for the clutch mechanism 18;
furthermore, instead of lever operation, the clutch mechanism 18
may be magnetically operated, or hydraulically operated.
[0046] The rotating machine 11 is driven by the power of the
driving source 16 that is provided separately from the
aforementioned thermal engine 4 (binary cycle); examples include a
fluid machine such as a pump or a compressor that is operated when
a member within the apparatus is rotated by the power of the
driving source 16, or a member that is rotated using the rotational
driving force of an engine (the driving source 16) in a machine
that uses the engine (driving source 16), such as an automobile or
a marine vessel. Furthermore, an electricity generator 25 that
generates electricity using, for example, a gasoline engine and a
diesel engine as a driving source 16 may be used in such a rotating
machine 11. Further, an electric motor may be used as a driving
source 16 of the rotating machine 11, rather than a gasoline
engine, a diesel engine, or the like that employs internal
combustion.
[0047] Incidentally, the power generation apparatus 1 according to
the present invention can be embodied in a variety of ways as
illustrated in the first through sixth embodiments, depending on
how the power transmission path 15 spanning from the expander 3 of
the thermal engine 4 to the rotor of the rotating machine 11 is
arranged, and depending on whether or not the electricity generator
25 is provided.
[0048] As shown in FIG. 1, the power generation apparatus 1
according to the first embodiment includes the power transmission
path 15, which transmits the rotational driving force extracted to
the exterior of the housing 5 via the magnetic coupling 10 to the
rotating machine 11 via the slave shaft 9 of the power transmission
shaft 6. The configuration is such that the speed variator 17,
clutch mechanism 18, and driving source 16 are arranged in the
power transmission path 15 in that order from the magnetic coupling
10, and the rotational driving force is ultimately outputted to a
pump rotor 26 through the driving source 16. In other words, the
power generation apparatus according to the first embodiment is an
example of an apparatus in which an electric motor, or in other
words, the driving source 16, is present in the power transmission
path 15 that spans from the expander 3 to the pump rotor 26, and in
which the electricity generator 25 is not provided.
[0049] With the aforementioned power generation apparatus 1, the
rotational driving force extracted to the exterior of the housing 5
via the magnetic coupling 10 is first transmitted to the speed
variator 17 via the slave shaft 9 that is connected to the magnetic
coupling 10. After the rotational speed has been changed by the
speed variator 17 to the optimal speed for driving the rotating
machine 11, the post-change rotational driving force is transmitted
(inputted) to the driving source 16 of the rotating machine 11 via
the clutch. The rotating machine 11 according to the present
embodiment transmits the power of the driving source 16 to the pump
rotor 26 via the pump drive shaft 23, and a pump that operates
(sucks, or exhausts) is implemented by rotationally driving the
pump rotor 26.
[0050] As described above, the rotational driving force whose speed
has been changed by the speed variator 17 is directly inputted to
the pump drive shaft 23 in tandem with the rotational driving force
of the driving source 16 itself, and power resulting from combining
the rotational driving force extracted to the exterior of the
housing 5 via the magnetic coupling 10 and the power generated by
the driving source 16 is transmitted to the pump drive shaft 23; as
a result, the pump is driven by a combination of the two rotational
driving forces from the different generation sources.
[0051] To rephrase, the power generation apparatus 1 according to
the first embodiment is an example of an apparatus that uses the
rotational driving force extracted to the exterior of the housing 5
via the magnetic coupling 10 as auxiliary power when driving a pump
using the power from an electric motor. Using such a power
generation apparatus 1 makes it possible to use the rotational
driving force extracted to the exterior of the housing 5 via the
magnetic coupling 10 as auxiliary power, which has the effect of
reducing the power consumed by the electric motor, which is a
driving source 16. Meanwhile, in the case where a gasoline engine
is used as the driving source 16 instead of an electric motor,
there is an effect of improving the fuel efficiency.
Second Embodiment
[0052] Although the magnetic coupling 10, speed variator 17, clutch
mechanism 18, driving source 16, and pump rotor 26 are arranged in
the power transmission path 15 in that order in the aforementioned
first embodiment, it is also possible to reverse the arrangement of
the driving source 16 and the pump rotor 26 in the power
transmission path 15.
[0053] In other words, as shown in FIG. 2, the power generation
apparatus 1 according to a second embodiment is an example of an
apparatus in which the speed variator 17 and the driving source 16,
which is an electric motor, are separately connected to the
respective ends of the pump drive shaft 23 of the pump rotor 26,
and in which the electricity generator 25 is not provided.
[0054] Even if such a power generation apparatus 1 is employed, the
rotational driving force extracted to the exterior of the housing 5
via the magnetic coupling 10 can be used as auxiliary power, which
has the effect of reducing the amount of power consumed by the
driving source 16, improving the fuel efficiency thereof, or the
like.
Third Embodiment, Fourth Embodiment
[0055] Although the aforementioned first and second embodiments
describe examples of the power generation apparatus 1 that is not
provided with the electricity generator 25, the following third
through sixth embodiments describe examples of the power generation
apparatus 1 that is provided with the electricity generator 25.
[0056] In other words, as shown in FIG. 3, the power generation
apparatus 1 according to the third embodiment includes the
electricity generator 25 in the power transmission path 15, in a
location that is closer to the rotating machine 11 than the speed
variator 17. Electricity is first generated by rotating the
electricity generator 25 using the rotational driving force
extracted to the exterior of the housing 5 via the magnetic
coupling 10, and the rotational driving force that remains after
the electricity generation is transmitted to the rotating machine
11; this remaining rotational driving force is used as auxiliary
power for supplementing the power of the driving source 16.
[0057] Using such a power generation apparatus 1 makes it possible,
in an electricity generation cycle that generates electricity using
a binary cycle (the thermal engine 4), to use the rotational
driving force that was not used in the generation of electricity by
the electricity generation cycle as auxiliary power for
supplementing the power of the driving source 16 in the rotating
machine 11, which has the effects of reducing the amount of power
consumed by the driving source 16, improving the fuel efficiency
thereof, or the like.
[0058] Meanwhile, if the arrangement of the driving source 16 and
the pump rotor 26 in the power transmission path 15 according to
the third embodiment shown in FIG. 3 is reversed, the power
generation apparatus 1 according to the fourth embodiment, shown in
FIG. 4, is obtained.
[0059] It should be noted that in the power generation apparatus 1
according to the fourth embodiment, a motor 27 having an
electricity generation function is used both as an electric motor,
which is the driving source 16 of the rotating machine 11, and as
the electricity generator 25. This motor 27 having an electricity
generation function operates as an electric motor when there is
insufficient power for rotationally driving the pump rotor 26, and
operates as the electricity generator 25 when there is power left
over.
[0060] Using such a power generation apparatus 1 makes it possible,
in an electricity generation cycle that generates electricity using
a binary cycle (the thermal engine 4), to use the rotational
driving force that was not used in the generation of electricity by
the electricity generation cycle as auxiliary power for
supplementing the power of the driving source 16 in the rotating
machine 11, which has the effects of reducing the amount of power
consumed by the driving source 16, improving the fuel efficiency
thereof, or the like.
Fifth Embodiment, Sixth Embodiment
[0061] Although the electricity generator 25 is provided outside
the housing 5 of the expander 3 in the aforementioned third and
fourth embodiments, it should be noted that the electricity
generator 25 can be provided within the housing 5 of the expander
3, as illustrated in the following fifth and sixth embodiments.
[0062] For example, as shown in FIGS. 5 and 6, the electricity
generator 25 is provided in the power transmission path 15 (that
is, in the drive shaft 8) between the driving unit 2 (screw rotor
2) of the expander 3 and the outer cylinder 20 of the magnetic
coupling 10, and electricity is generated thereby; the rotational
driving force not used to generate electricity can also be
extracted to the exterior of the housing 5 and used as auxiliary
power for driving the rotating machine 11.
[0063] Using such a power generation apparatus 1 makes it possible
to use the rotational driving force that was not used in the
generation of electricity by the electricity generation cycle as
auxiliary power for supplementing the power of the driving source
16 in the rotating machine 11, which has the effects of reducing
the amount of power consumed by the driving source 16, improving
the fuel efficiency thereof, or the like.
Seventh Embodiment
[0064] The rotating machine 11, which is the target of the driving
carried out by the power generation apparatus 1 according to the
present invention, often produces a large amount of heat during
rotational operations.
[0065] For example, in the case where the rotating machine 11 is a
gas compressor 50 that compresses a gas V such as air to a high
pressure, a high-pressure gas V that has a high temperature and an
extremely high amount of heat is produced through adiabatic
compression. At this time, the high-pressure gas V that is produced
is cooled, by a cooling device such as a cooler 54, to a required
temperature based on the purpose of use. In other words, the amount
of heat produced by the gas compressor 50, or the rotating machine
11, has typically been released as waste heat.
[0066] Accordingly, in the present invention, heat produced by the
rotating machine 11 is introduced to the power generation apparatus
1, thus reusing useful heat.
[0067] A seventh embodiment of the power generation apparatus 1
according to the present invention (that is, reusing heat from the
rotating machine 11) will be described based on the drawings.
[0068] As shown in FIG. 7, the configuration of the power
generation apparatus 1 according to the seventh embodiment is
essentially the same as the apparatus according to the first
embodiment (see FIG. 1) in the following points.
[0069] That is, the power generation apparatus 1 according to the
seventh embodiment, or to rephrase, the thermal engine 4 according
to the seventh embodiment, uses a mechanism that employs a binary
cycle.
[0070] To be more specific, the thermal engine 4 includes: the
evaporator 13 that evaporates the liquid working fluid T (working
medium) using heat supplied from a heat source; the expander 3 that
rotationally drives the driving unit 2 by expanding the vapor of
the working fluid T evaporated by the evaporator 13; the condenser
12 that converts the vapor of the working fluid T expanded by the
expander 3 into liquid working fluid T by condensing that vapor;
and the medium circulation pump 14 that circulates the liquid
working fluid T condensed by the condenser 12 by
pressure-transferring the working fluid T to the evaporator 13.
[0071] The evaporator 13, the expander 3, the condenser 12, and the
medium circulation pump 14 are connected in that order by a
closed-loop circulation pipe 55 that circulates the working fluid T
(a low-boiling point organic medium, such as alternative Freon
(R245fa) or the like).
[0072] Furthermore, the driving unit 2 (a screw rotor) that
configures the expander 3 is housed within the thermal engine 4 in
a sealed state, and the power transmission shaft 6, which extracts
the rotational driving force produced by the driving unit 2
rotating to the exterior of the thermal engine 4, is provided with
the magnetic coupling 10. These configurations are essentially the
same as in the first embodiment. The configuration in which
rotational driving force produced by the expander 3 is transmitted
to the exterior of the thermal engine 4 via the magnetic coupling
10, and is sent to the rotating machine 11 and used as auxiliary
power for the rotating machine 11, is also the same.
[0073] In addition, providing the speed variator 17 that changes
the rotational speed of the power transmission shaft 6 and
transmits the auxiliary power downstream, and the clutch mechanism
18 that controls the transmission state of the power to the
rotating machine 11, between the expander 3 and the rotating
machine 11, is also the same in the seventh embodiment.
[0074] However, the configuration of the power generation apparatus
1 according to the seventh embodiment differs greatly from the
first embodiment in the following points.
[0075] First, a "gas compressor", which pressurizes a supplied gas
V to a high pressure, is employed as the rotating machine 11 that
is the target of the power generation apparatus 1.
[0076] The gas compressor 50 introduces a gas V (at, for example,
approximately 30.degree. C.) from the exterior and adiabatically
compresses the introduced gas V by rotating compression means
(rotors) 51 and 52 within the gas compressor 50, thus producing a
high-pressure gas V. At this time, the produced gas V rises in
temperature (to, for example, approximately 180.degree. C.), and
thus has a high amount of heat.
[0077] The gas compressor 50 according to the seventh embodiment
includes multiple compression means (a first-stage compression
means 51 and a second-stage compression means 52) in an axially
serially connected state and a motor 53 that drives the multiple
compression means, and is an oil-free multi-stage gas compressor
that does not use a lubrication oil. The motor 53 that produces the
driving force is an electric motor. However, a hydraulic motor that
drives using a hydraulic pump may be used as the motor 53.
[0078] With this gas compressor 50, the gas V introduced from the
exterior is compressed by the first-stage compression means,
resulting in a high-pressure gas V; this gas V first flows into a
primary side of a first evaporator 56 (details will be given later)
provided in an auxiliary power transmission apparatus 1. The gas V
that has flowed through the first evaporator 56 is then transferred
to the second-stage compression means and is compressed further,
resulting in a high-pressure gas V. The high-pressure gas V that is
produced flows into a primary side of a second evaporator 57
(details will be given later) provided in the auxiliary power
transmission apparatus 1, and the gas V that flows through the
second evaporator 57 is cooled, by a cooling device such as a
cooler 54, to a required temperature based on the purpose of
use.
[0079] The gas compressor 50 (rotating machine 11) described thus
far can also be operated by the motor 53 alone. The expander 3
according to the present embodiment is additionally attached to the
gas compressor 50, and assists the gas compressor 50 with
driving.
[0080] Meanwhile, the thermal engine 4 itself according to the
seventh embodiment differs from that in the first embodiment
according to the following points.
[0081] In other words, the thermal engine 4 includes the first
evaporator 56 and the second evaporator 57, which are disposed in
parallel. That is, two or more of the evaporators 13 are provided
on the downstream side of the medium circulation pump 14.
[0082] Parallel pipes that branch from the circulation pipe 55
connected to the downstream side of the medium circulation pump 14
are respectively connected to the input sides of the first
evaporator 56 and the second evaporator 57. Pipes that extend from
the output sides of the first evaporator 56 and the second
evaporator 57, respectively, are connected to the circulation pipe
55 on the upstream side of the expander 3.
[0083] The first evaporator 56 uses the heat of the high-pressure
gas V produced by the first-stage compression means (that is,
carries out thermal exchange) in order to evaporate the liquid
working fluid T, thus producing a vaporous working fluid T.
Meanwhile, like the first evaporator 56, the second evaporator uses
the heat of the high-pressure gas V produced by the second-stage
compression means 52 (that is, carries out thermal exchange) in
order to evaporate the liquid working fluid T, thus producing a
vaporous working fluid T. The vaporous working fluid T produced in
this manner is sent to the expander 3 through the circulation pipe
55 that is connected to the output sides of the first evaporator 56
and the second evaporator 57.
[0084] The expander 3 expands the vaporous working fluid T produced
by the first evaporator 56 and the second evaporator 57, and the
driving unit 2 rotationally drives using the pressure difference in
the pre- and post-expansion working fluid T.
[0085] The rotational driving force produced by the expander 3 is
extracted to the exterior of the thermal engine 4 via the magnetic
coupling 10, and is transferred to the speed variator 17 (reducer).
The speed variator 17 changes the rotational driving force to a
rotational speed that is optimal for driving the gas compressor 50,
and the post-change rotational driving force is then transmitted to
the motor 53 of the gas compressor 50 via the clutch mechanism
18.
[0086] Through this configuration, the heat of the high-pressure
gas V produced by the gas compressor 50 can be reused rather than
discarded, and the rotational driving force produced by the driving
unit 2 of the expander 3 can be used as auxiliary power for the
motor 53 provided in the gas compressor 50, which makes it possible
to realize an energy-efficient gas compressor 50.
[0087] Note that the behavior of the working fluid T following the
expansion performed by the expander 3 is essentially the same as
described in the first embodiment, and thus descriptions will be
omitted here.
[0088] Although the descriptions of the seventh embodiment describe
the compression means 51 and 52 of the gas compressor 50 as being
in an axially serially connected state, another state (non-axially
serially connected) can be employed as a specific connection
method, as shown in FIG. 8.
[0089] For example, as shown in FIG. 8A, a configuration may be
employed in which the speed variator 17 and the clutch mechanism 18
are connected to the output shaft of the expander 3 of the
auxiliary power generation apparatus and the motor 53 of the gas
compressor 50 is connected to the output shaft of the clutch
mechanism 18. A bull gear 58 is connected to the drive shaft of the
motor 53. Two pinion gears 59 interlock with the bull gear 58, and
the rotational driving force of the bull gear 58 is transmitted to
the respective pinion gears 59. The two pinion gears 59 are
disposed on either side of the bull gear 58, and are connected to
the drive shafts of the first-stage compression means 51 and the
second-stage compression means 52, respectively.
[0090] Through this, the rotational driving force produced by the
expander 3 is transmitted to the bull gear along with the
rotational driving force of the motor 53, and is then transmitted
to the first-stage compression means 51 and the second-stage
compression means 52 through the pinion gears 59 that interlock
with the bull gear 58.
[0091] Meanwhile, as shown in FIG. 8B, a configuration in which a
pinion gear (a first pinion gear 60) is connected to the output
shaft of the expander 3 of the auxiliary power generation
apparatus, and the first pinion gear 60 interlocks with the bull
gear 58, can also be employed. The bull gear 58 is connected to the
drive shaft of the motor 53.
[0092] Another pinion gear (a second pinion gear 61) interlocks
with the bull gear 58 attached to the drive shaft of the motor 53,
and the second pinion gear 61 is connected to the drive shaft of
the first-stage compression means 51. Furthermore, yet another
pinion gear (a third pinion gear 62) interlocks with the bull gear
58, and the third pinion gear 62 is connected to the drive shaft of
the second-stage compression means 52.
[0093] Through this, the rotational driving force produced by the
expander 3 can be transmitted to the bull gear 58 to which the
driving force from the motor 53 is transmitted, and can then be
transmitted to the pinion gears 59 that interlock via the bull gear
58; the rotational driving force is then transmitted to the
first-stage compression means 51 and the second-stage compression
means 52.
[0094] Note that the descriptions disclosed in the above embodiment
are to be understood as being in all ways exemplary and in no way
limiting. The scope of the present invention is defined not by the
aforementioned descriptions but by the scope of the appended
claims, and all changes that fall within the same essential spirit
as the scope of the claims are intended to be included therein as
well. For example, although not particularly mentioned in the
aforementioned embodiments, a speed variator need not be provided
in the power transmission path spanning from the expander to the
rotating machine in the case where the rotational speed of a
mechanical expander is inputted directly into the rotating machine.
In addition, the numbers of driving-side magnets and slave-side
magnets in the magnetic coupling are not limited to two, and more
than two magnets may be provided for each. Furthermore, items that
are not explicitly disclosed in the embodiments disclosed above,
such as operating conditions, working conditions, various types of
parameters, the dimensions, weights, volumes, and the like of
constituent elements use values that can easily be assumed by one
skilled in the art without departing from the scope that one
skilled in the art normally works within.
* * * * *