U.S. patent application number 13/885158 was filed with the patent office on 2013-09-12 for double-screw liquid pump.
This patent application is currently assigned to SHANGHAI POWER TECH. SCREW MACHINERY CO., LTD.. The applicant listed for this patent is Yan Tang. Invention is credited to Yan Tang.
Application Number | 20130236334 13/885158 |
Document ID | / |
Family ID | 43575066 |
Filed Date | 2013-09-12 |
United States Patent
Application |
20130236334 |
Kind Code |
A1 |
Tang; Yan |
September 12, 2013 |
DOUBLE-SCREW LIQUID PUMP
Abstract
A double-screw liquid pump is provided, which is applicable to
an Organic Rankin Cycle (ORC). The double-screw liquid pump
includes a semi-sealed or fully sealed shell, and the shell
includes a first cavity and a second cavity isolated from each
other. A motor is disposed in the first cavity, and a main body
part of a double-screw is disposed in the second cavity. At least
one rotor of the double-screw is fixedly connected to a rotor of
the motor, and the double-screw rotates through driving of the
motor. A liquid refrigerant injection inlet and a refrigerant
outlet are disposed on the first cavity, and the motor is cooled
through evaporation of a liquid refrigerant; a liquid inlet and a
liquid outlet are disposed on the second cavity. In the
double-screw liquid pump applied to the ORC provided in the present
invention, since a resistance torque of the female rotor is very
small, the liquid pump does not wear even when the liquid viscosity
is very low, contributing to good reliability, and thereby
improving power generation efficiency of the ORC. In addition, the
semi-sealed or fully sealed shell can effectively prevent leakage
of the refrigerant.
Inventors: |
Tang; Yan; (Shanghai,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Tang; Yan |
Shanghai |
|
CN |
|
|
Assignee: |
SHANGHAI POWER TECH. SCREW
MACHINERY CO., LTD.
Shanghai
CN
|
Family ID: |
43575066 |
Appl. No.: |
13/885158 |
Filed: |
November 30, 2010 |
PCT Filed: |
November 30, 2010 |
PCT NO: |
PCT/CN2010/079291 |
371 Date: |
May 13, 2013 |
Current U.S.
Class: |
417/366 |
Current CPC
Class: |
F04C 13/00 20130101;
F04C 15/008 20130101; F04C 2/16 20130101; F04C 15/0038 20130101;
F04C 23/008 20130101; F04C 29/045 20130101; F01C 21/10 20130101;
F04C 15/0096 20130101; F04C 2240/30 20130101 |
Class at
Publication: |
417/366 |
International
Class: |
F04C 29/04 20060101
F04C029/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2010 |
CN |
201010548653.5 |
Claims
1. A double-screw liquid pump comprising a semi-sealed or fully
sealed shell, wherein the shell comprises a first cavity and a
second cavity isolated from each other; a motor is disposed in the
first cavity, and a main body part of a double-screw is disposed in
the second cavity; at least one rotor of the double-screw is
fixedly connected to a rotor of the motor, and the double-screw
rotates through driving of the motor; a liquid refrigerant
injection inlet and a refrigerant outlet are disposed on the first
cavity; and the motor is cooled through evaporation of a liquid
refrigerant; and a liquid inlet and a liquid outlet are disposed on
the second cavity.
2. The double-screw liquid pump as in claim 1, wherein the
double-screw comprises a male rotor and a female rotor; and a first
end of the male rotor is fixedly connected to the rotor of the
motor.
3. The double-screw liquid pump as in claim 2, wherein the male
rotor comprises a rotor part and a connection part which are
integrally designed; the rotor part is disposed in the second
cavity and coordinates with the female rotor; the connection part
extends into the motor in the first cavity; the first cavity and
the second cavity are isolated from each other through an isolation
mechanism, so that a hole is formed between the first cavity and
the second cavity; the connection part passes through the hole and
enters the first cavity, and an end of the connection part away
from the rotor part is fixedly connected to the rotor of the
motor.
4. The double-screw liquid pump as in claim 3, wherein a first male
rotor bearing is disposed at a second end of the male rotor away
from the motor, and female rotor bearings are separately disposed
at two ends of the female rotor.
5. The double-screw liquid pump as in claim 4, wherein a second
male rotor bearing is disposed at the connection part and between
the rotor part of the male rotor and the rotor of the motor.
6. The double-screw liquid pump as in claim 5, wherein the
connection part and an end of the second male rotor bearing close
to the rotor of the motor are sealed through a shaft seal.
7. The double-screw liquid pump as in claim 1, wherein the motor is
an inverter motor or a motor with a fixed rotating speed.
Description
BACKGROUND OF THE PRESENT INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to the field of Organic Rankin
Cycle (ORC) technology, specifically to an ORC power generation
system, and more specifically to a double-screw liquid pump of the
ORC power generation system.
[0003] 2. Description of Related Arts
[0004] Referring to FIG. 1, FIG. 1 is a typical ORC, which includes
an expander 1', a generator 2', an evaporator 3', a liquid pump 4'
and a condenser 5'.
[0005] A low-temperature and low-pressure liquid refrigerant is
pressurized in the liquid pump 4', and then enters the evaporator
3' to be evaporated through heating until the refrigerant becomes
an overheated gas (high temperature and high pressure). The
overheated gas enters the expander 1' to work through expansion, so
as to drive the generator 2' to generate power. After working, the
low-temperature and low-pressure gas enters the condenser 5' and is
condensed to liquid, and then flows back into the liquid pump 4',
thus completing a cycle.
[0006] Most of the existing liquid pumps are open-type gear pumps
or centrifugal pumps. The gear pump has the following defects: in
the gear pump, one gear always drives another gear, and half of the
consumed work is consumed during a driving process; meanwhile, in
the ORC cycle, liquid viscosity is usually low, and the gear wears
easily. The centrifugal pump has the following defect: after the
centrifugal pump sucks the liquid, a pressure during the suction
process is decreased, and the liquid evaporates easily, which
causes efficiency of the centrifugal pump to decrease, thereby
affecting efficiency of the entire ORC cycle. The open-type liquid
pump has the following defect: the refrigerant leaks easily through
a shaft seal.
SUMMARY OF THE PRESENT INVENTION
[0007] The technical problem to be solved by the present invention
is to provide a double-screw liquid pump, in which a resistance
torque of a female rotor is very small, and the liquid pump does
not wear even when the liquid viscosity is very low, contributing
to good reliability.
[0008] In order to solve the above technical problem, the present
invention adopts the following technical solution.
[0009] A double-screw liquid pump is provided, comprising a
semi-sealed or fully sealed shell, wherein the shell comprises a
first cavity and a second cavity isolated from each other; a motor
is disposed in the first cavity, and a main body part of a
double-screw is disposed in the second cavity; at least one rotor
of the double-screw is fixedly connected to a rotor of the motor,
and the double-screw rotates through driving of the motor; a liquid
refrigerant injection inlet and a refrigerant outlet are disposed
on the first cavity, and the motor is cooled through evaporation of
the liquid refrigerant; a liquid inlet and a liquid outlet are
disposed on the second cavity.
[0010] As a preferential solution of the present invention, the
double-screw comprises a male rotor and a female rotor, and a first
end of the male rotor is fixedly connected to the rotor of the
motor.
[0011] As a preferential solution of the present invention, the
male rotor comprises a rotor part and a connection part which are
integrally designed; the rotor part is disposed in the second
cavity and coordinates with the female rotor; the connection part
extends into the motor in the first cavity; the first cavity and
the second cavity are isolated from each other through an isolation
mechanism, so that a hole is formed between the first cavity and
the second cavity; the connection part passes through the hole and
enters the first cavity, and an end of the connection part away
from the rotor part is fixedly connected to the rotor of the
motor.
[0012] As a preferential solution of the present invention, a first
male rotor bearing is disposed at a second end of the male rotor
away from the motor, and female rotor bearings are separately
disposed at two ends of the female rotor.
[0013] As a preferential solution of the present invention, a
second male rotor bearing is disposed at the connection part and
between the rotor part of the male rotor and the rotor of the
motor.
[0014] As a preferential solution of the present invention, the
connection part and an end of the second male rotor bearing close
to the rotor of the motor are sealed through a shaft seal.
[0015] As a preferential solution of the present invention, the
motor is an inverter motor or a motor with a fixed rotating
speed.
[0016] The present invention has the following beneficial effects:
in the double-screw liquid pump applied to the ORC provided in the
present invention, since a resistance torque of the female rotor is
very small, the liquid pump does not wear even when the liquid
viscosity is very low, contributing to good reliability, and
thereby improving power generation efficiency of the ORC. In
addition, the semi-sealed or fully sealed shell can effectively
prevent leakage of the refrigerant.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic view of composition of an ORC power
generation system.
[0018] FIG. 2 is a schematic view of composition of an ORC power
generation system using the present invention.
[0019] FIG. 3 is a sectional view of a double-screw liquid pump in
a vertical direction consistent with the present invention.
[0020] FIG. 4 is a sectional view of a double-screw liquid pump in
a horizontal direction consistent with the present invention.
[0021] FIG. 5 is a sectional view of the male and female motors of
a double-screw liquid pump consistent with the present
invention.
LIST OF REFERENCE NUMERALS
[0022] 1' Expander [0023] 2' Generator [0024] 3' Evaporator [0025]
4' Liquid pump 5' Condenser [0026] 1 Expander [0027] 2 Generator
[0028] 3 Evaporator [0029] 4 Liquid pump [0030] 5 Condenser [0031]
401 Motor [0032] 402 Male rotor [0033] 403 Female rotor [0034] 4041
First male rotor bearing [0035] 4042 Second male rotor bearing
[0036] 405 Female rotor bearing [0037] 406 Seal ring [0038] 407
Liquid inlet [0039] 408 Liquid outlet [0040] 409 Refrigerant
injection inlet [0041] 410 Refrigerant outlet [0042] 411 Shaft
seal
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] Exemplary embodiments of the present invention are described
in detail with reference to the accompanying drawings below.
Embodiment 1
[0044] Referring to FIG. 2, FIG. 2 shows an ORC power generation
system using the present invention. The ORC power generation system
includes a condenser 5, a liquid pump 4, an evaporator 3, an
expander 1, and a generator 2. The main improvement of the present
invention is the liquid pump 4. In this embodiment, the liquid pump
4 is a double-screw liquid pump 4.
[0045] Referring to FIG. 3 and FIG. 4, the double-screw liquid pump
4 includes a semi-sealed or fully sealed shell. The shell is formed
of multiple components, and a seal ring 406 is disposed at each gap
between components. The shell includes a first cavity and a second
cavity isolated from each other. A motor 401 is disposed in the
first cavity, and a main body part of a double-screw is disposed in
the second cavity. At least one rotor of the double-screw is
fixedly connected to a rotor of the motor. The double-screw rotates
through driving of the motor 401. A dynamic source of the motor 401
may be from electric energy generated by the ORC power generation
system. A liquid refrigerant injection inlet 409 and a refrigerant
outlet 410 are disposed on the first cavity, and the motor 401 is
cooled through evaporation of the liquid refrigerant. A liquid
inlet 407 and a liquid outlet 408 are disposed on the second
cavity. The motor may be an inverter motor or a motor of a fixed
rotating speed, and definitely may be an ordinary motor.
[0046] The double-screw liquid pump includes a male rotor 402, and
a female rotor 403. A first end of the male rotor 402 is fixedly
connected to the rotor of the motor 401. The male rotor 402
includes a rotor part and a connection part which are integrally
designed. The rotor part is disposed in the second cavity and
coordinates with the female rotor 403. The connection part extends
into the motor 401 in the first cavity. The first cavity and the
second cavity are isolated from each other through an isolation
mechanism, so that a hole is formed between the first cavity and
the second cavity; the connection part passes through the hole and
enters the first cavity, and an end of the connection part away
from the rotor part is fixedly connected to the rotor of the motor
401.
[0047] A first male rotor bearing 4041 is disposed at a second end
of the male rotor 402 away from the motor 401. Female rotor
bearings 405 are separately disposed at two ends of the female
rotor 403. A second male rotor bearing 4042 is disposed at the
connection part and between the rotor part of the male rotor and
the rotor of the motor. The connection part and an end of the
second male rotor bearing 4042 close to the rotor of the motor are
sealed through a shaft seal 411.
[0048] In conclusion, in the fully sealed or semi-sealed
double-screw liquid pump applied to the ORC power generation system
provided in the present invention, since a resistance torque of the
female rotor is very small, the liquid pump does not wear even when
the liquid viscosity is very low, contributing to good reliability,
and thereby improving power generation efficiency of the ORC. In
addition, the semi-sealed or fully sealed shell can effectively
prevent leakage of the refrigerant.
[0049] Herein, the description and application of the present
invention are illustrative, and the scope of the present invention
is not intended to be limited to the above embodiments. Variations
and changes to the embodiments disclosed herein are possible.
Replacement made to the embodiments and equivalent parts are
well-known to persons skilled in the art. It should be known to
persons skilled in the art that, the present invention can be
implemented in other forms, structures, arrangements, ratios and
through other components, materials, and parts without departing
from the script or essential features of the present invention.
Other variations and changes may be made to the embodiments
disclosed herein without departing from the scope and script of the
present invention.
* * * * *