US7454910B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Waste heat recovery system of heat source, with Rankine cycle
Assignee: Denso Corp
•
Filing: 2005-02-08
•
Granted: 2008-11-25
•
Expires: 2025-02-08
Abstract
Abstract A waste heat recovery system of an engine has a cooling water circuit and a Rankine cycle. Cooling water is circulated between the engine and a radiator in the cooling water circuit. The Rankine cycle has a heater and an expansion device. The heater performs heat exchange between the cooling water heated by the engine and an operation fluid so as to heat the operation fluid in the Rankine cycle. The expansion device expands the heated operation fluid, so as to generate driving power. The heater is arranged in a bypass circuit so as to be in parallel with the radiator with respect to the cooling water flow. Thus, waste heat of the cooling water heated by the engine can be effectively recovered without reducing a cooling capacity of the radiator.
Inventors
- 👤 Shinichi Hamada
- 👤 Minoru Sasaki
- 👤 Atsushi Inaba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:51
CPC Classifications
F; F02; F02G; F02G5/00; F01; F01K; F01K23/00; F01K23/02; F01K23/06; F01K23/065; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
410 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power, wherein the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the system further comprising: a temperature sensor for sensing an actual temperature of the thermal medium; a first pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a first switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger, at least one of a discharge capacity of the first pumping unit and the flow distribution distributed by the first switching unit being variable; a control unit for controlling at least one of the first pumping unit and the first switching unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein the control unit includes means for calculating a difference between a target thermal medium temperature and the actual temperature of the thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the first switching unit so as to decrease a distribution amount of thermal medium flowing into the cooling heat exchanger when the distribution amount is not substantially zero; and when the difference is greater than a second threshold, which is higher than the first threshold, the control unit determines that the temperature of the heat source is excessively high, and controls the first pumping unit so as to increase the discharge capacity when the first pumping unit has an extra discharge capacity.
Claim 2
Dependent Claim
410 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power, wherein the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the system further comprising: a temperature sensor for sensing an actual temperature of the thermal medium; a first pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a first switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger, at least one of a discharge capacity of the first pumping unit and the flow distribution distributed by the first switching unit being variable; a control unit for controlling at least one of the first pumping unit and the first switching unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein the control unit includes means for calculating a difference between a target thermal medium temperature and the actual temperature of the thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the first switching unit so as to decrease a distribution amount of thermal medium flowing into the cooling heat exchanger when the distribution amount is not substantially zero; and when the difference is greater than a second threshold, which is higher than the first threshold, the control unit determines that the temperature of the heat source is excessively high, and controls the first pumping unit so as to increase the discharge capacity when the first pumping unit has an extra discharge capacity.
Claim 3
Dependent Claim
77 words
The waste heat recovery system of the heat source according to claim 1 , further comprising: a bypass circuit that is branched from a section of the thermal medium circulating circuit where thermal medium is circulated between the heat source and the cooling heat exchanger to bypass the cooling heat exchanger, and merged with a downstream side of the cooling heat exchanger in the thermal medium circulating circuit, wherein the heater is arranged in the bypass circuit.
Claim 4
Dependent Claim
56 words
The waste heat recovery system of the heat source according to claim 1 , further comprising: a heater circuit that includes a heating heat exchanger which performs heat exchange between blown air and thermal medium heated by the heat source so as to heat the blown air, wherein the heater is arranged in the heater circuit.
Claim 5
Dependent Claim
39 words
The waste heat recovery system of the heat source according to claim 1 , wherein: the heater circuit further includes a second pumping unit for circulating the thermal medium; and the second pumping unit has a variable discharge capacity.
Claim 6
Dependent Claim
38 words
The waste heat recovery system of the heat source according to claim 4 , wherein: the heat source is a rotating device; and the second pumping unit is controlled based on a rotation speed of the rotating device.
Claim 7
Dependent Claim
57 words
The waste heat recovery system of the heat source according to claim 1 , further comprising: a second switching unit for opening and closing a flow passage of thermal medium flowing into the heater, wherein the second switching unit is located on one of an inlet side of the heater and an outlet side of the heater.
Claim 8
Dependent Claim
33 words
The waste heat recovery system of the heat source according to claim 6 , wherein the second switching unit is provided to change a flow amount of thermal medium flowing into the heater.
Claim 9
Dependent Claim
40 words
The waste heat recovery system of the heat source according to claim 7 , further comprising: means for forcibly closing the second switching unit when a temperature of the thermal medium is equal to or greater than a predetermined temperature.
Claim 10
Dependent Claim
89 words
The waste heat recovery system of the heat source according to claim 1 , further comprising: a driving device that is disposed to obtain a driving power generated in the heat source; and a refrigerant cycle that includes a compressor driven by the driving device for compressing and circulating refrigerant, wherein: the expansion device is mechanically coupled with the compressor; and the expansion device is disposed to add the driving power generated in the expansion device to the compressor, when the driving power is generated in the expansion device.
Claim 11
Dependent Claim
49 words
The waste heat recovery system of the heat source according to claim 1 , further comprising: a second pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium into the heater in an auxiliary manner, wherein the second pumping unit has a variable discharge capacity.
Claim 12
Dependent Claim
38 words
The waste heat recovery system of the heat source according to claim 10 , wherein: the heat source is a rotating device; and the first pumping unit is controlled based on a rotation speed of the rotating device.
Claim 13
Dependent Claim
39 words
The waste heat recovery system of the heat source according to claim 10 , wherein at least one of a discharge capacity of the second pumping unit and the flow distribution distributed by the first switching unit is variable.
Claim 14
Dependent Claim
250 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a first pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a second pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium into the heater in an auxiliary manner; and wherein: the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger; and the second pumping unit has a variable discharge capacity, wherein the heat source is an internal combustion engine, the first pump has a variable discharge capacity, which is substantially in proportion to a rotation speed of the internal combustion engine, and when the rotation speed is low: the discharging capacity of the first pump becomes small, and a discharging capacity of the second pump is controlled to become large.
Claim 15
Dependent Claim
250 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a first pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a second pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium into the heater in an auxiliary manner; and wherein: the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger; and the second pumping unit has a variable discharge capacity, wherein the heat source is an internal combustion engine, the first pump has a variable discharge capacity, which is substantially in proportion to a rotation speed of the internal combustion engine, and when the rotation speed is low: the discharging capacity of the first pump becomes small, and a discharging capacity of the second pump is controlled to become large.
Claim 16
Dependent Claim
81 words
The waste heat recovery system of the heat source according to claim 13 , further comprising: a switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger, wherein at least one of a discharge capacity of the second pumping unit and the flow distribution distributed by the switching unit is variable.
Claim 17
Dependent Claim
49 words
The waste heat recovery system of the heat source according to claim 13 , further comprising: a control unit, wherein: the first pumping unit is mechanically coupled with the internal combustion engine, and the second pumping unit is electrically controlled based on a driving signal of the control unit.
Claim 18
Dependent Claim
365 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; a pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a temperature sensor for sensing an actual temperature of the thermal medium; a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger; a control unit for controlling the pumping unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein at least one of a discharge capacity of the pumping unit and the flow distribution distributed by the switching unit being variable, and the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the control unit includes means for calculating a difference between a target thermal medium temperature and the actual temperature of thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the pumping unit so as to decrease the discharge capacity of the pumping unit; and when the difference is greater than a second threshold that is larger than the first threshold, the control unit determines that the temperature of the heat source is excessively high, and controls the pumping unit so as to increase the discharge capacity.
Claim 19
Dependent Claim
365 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; a pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; and a temperature sensor for sensing an actual temperature of the thermal medium; a Rankine cycle including a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger; a control unit for controlling the pumping unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein at least one of a discharge capacity of the pumping unit and the flow distribution distributed by the switching unit being variable, and the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the control unit includes means for calculating a difference between a target thermal medium temperature and the actual temperature of thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the pumping unit so as to decrease the discharge capacity of the pumping unit; and when the difference is greater than a second threshold that is larger than the first threshold, the control unit determines that the temperature of the heat source is excessively high, and controls the pumping unit so as to increase the discharge capacity.
Claim 20
Dependent Claim
61 words
The waste heat recovery system of the heat source according to claim 16 , further comprising: a cooling water temperature detecting unit that is disposed on a downstream side of the heat source and disposed on an upstream side of both the cooling heat exchanger and the heater for detecting temperature of thermal medium, which is discharged from the heat source.
Claim 21
Dependent Claim
65 words
The waste heat recovery system of the heat source according to claim 16 , wherein: the switching unit is a switching valve including a thermostat, which responds to temperature of thermal medium flowing through the thermal medium circulating circuit, and the switching valve adjusts a flow distribution of thermal medium, which is to be introduced into the cooling heat exchanger, in response to the thermostat.
Claim 22
Dependent Claim
71 words
The waste heat recovery system of the heat source according to claim 16 , further comprising: a bypass circuit that is branched from the thermal medium circulating circuit to bypass the cooling heat exchanger and merged with the thermal medium circulating circuit at a merge section, wherein the switching unit is disposed on a downstream side of the cooling heat exchanger and disposed on an upstream side of the merge section.
Claim 23
Dependent Claim
24 words
The waste heat recovery system of the heat source according to claim 16 , wherein: the second threshold is greater than the first threshold.
Claim 24
Dependent Claim
74 words
The waste heat recovery system of the heat source according to claim 16 , further comprising: a bypass circuit, which is branched from the thermal medium circulating circuit at a branch section to bypass the cooling heat exchanger and merged with the thermal medium circulating circuit at a merge section, wherein: the pumping unit is disposed on an upstream side of the branch section and disposed on a downstream side of the merge section.
Claim 25
Dependent Claim
76 words
The waste heat recovery system of the heat source according to claim 18 , wherein: the switching valve adjusts a flow distribution of thermal medium in such a manner that a distribution amount of thermal medium distributed to the heater is prioritized compared with a distribution amount of thermal medium distributed to the cooling heat exchanger so as not to distribute thermal medium for increasing and decreasing the thermal medium distributed to the cooling heat exchanger.
Claim 26
Dependent Claim
373 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; a Rankine cycle including a temperature sensor for sensing an actual temperature of the thermal medium; a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger; a control unit for controlling the switching unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein at least one of a discharge capacity of the pumping unit and the flow distribution distributed by the switching unit being variable, and the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the control unit includes means for calculating a difference between a target thermal medium temperature and an actual temperature of the thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the switching unit so as to decrease a distribution amount of thermal medium distributed by the switching unit to the cooling heat exchanger; and when the difference is greater than a second threshold, which is higher than the first threshold, the control unit determines temperature of the heat source is excessively high, and controls the switching unit so as to increase the distribution amount.
Claim 27
Dependent Claim
373 words
A waste heat recovery system of a heat source that is cooled by a circulation of a thermal medium, the system comprising: a cooling heat exchanger for cooling the thermal medium, disposed in a thermal medium circulating circuit through which the thermal medium is circulated between the cooling heat exchanger and the heat source; and a pumping unit disposed in the thermal medium circulating circuit to circulate the thermal medium; a Rankine cycle including a temperature sensor for sensing an actual temperature of the thermal medium; a heater that performs heat exchange between an operation fluid and the thermal medium heated by the heat source so as to heat the operation fluid, and an expansion device that expands the operation fluid, which is heated by the heater to be evaporated, so as to generate a driving power; a switching unit disposed in the thermal medium circulating circuit to adjust a flow distribution between a flow amount of thermal medium to be introduced into the heater and a flow amount of thermal medium passing through the cooling heat exchanger; a control unit for controlling the switching unit based on a temperature of thermal medium discharged from the heat source in the thermal medium circulating circuit, wherein at least one of a discharge capacity of the pumping unit and the flow distribution distributed by the switching unit being variable, and the heater is arranged in parallel with the cooling heat exchanger in such a manner that the thermal medium flowing through the heater bypasses the cooling heat exchanger, the control unit includes means for calculating a difference between a target thermal medium temperature and an actual temperature of the thermal medium discharged from the heat source; when the difference is less than a first threshold, the control unit determines that a temperature of the heat source is excessively low, and controls the switching unit so as to decrease a distribution amount of thermal medium distributed by the switching unit to the cooling heat exchanger; and when the difference is greater than a second threshold, which is higher than the first threshold, the control unit determines temperature of the heat source is excessively high, and controls the switching unit so as to increase the distribution amount.
Claim 28
Dependent Claim
61 words
The waste heat recovery system of the heat source according to claim 23 , further comprising: a cooling water temperature detecting unit that is disposed on a downstream side of the heat source and disposed on an upstream side of both the cooling heat exchanger and the heater for detecting temperature of thermal medium, which is discharged from the heat source.
Claim 29
Dependent Claim
44 words
The waste heat recovery system of the heat source according to claim 23 , wherein: the pumping unit is a mechanical pump that is operated, without being controlled by the control unit based on the temperature detected using the cooling water temperature detecting unit.
Claim 30
Dependent Claim
24 words
The waste heat recovery system of the heat source according to claim 23 , wherein: the second threshold is greater than the first threshold.
Claim 31
Dependent Claim
69 words
The waste heat recovery system of the heat source according to claim 23 , wherein: when the difference is greater than the second threshold, the control unit controls the switching unit so as to increase the distribution amount of thermal medium distributed to the cooling heat exchanger, and the control unit controls the switching unit so as to decrease a distribution amount of thermal medium distributed to the heater.
Claim 32
Dependent Claim
69 words
The waste heat recovery system of the heat source according to claim 23 , wherein: when the difference is less than the first threshold, the control unit controls the switching unit so as to decrease the distribution amount of thermal medium distributed to the cooling heat exchanger, and the control unit controls the switching unit so as to increase a distribution amount of thermal medium distributed to the heater.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2011-11-25 | 2012-05-26 | 2012-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2015-11-25 | 2016-05-26 | 2016-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2019-11-25 | 2020-05-26 | 2020-11-25 | $7700.00 | Window Closed / Lapsed |