US4560104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coolant temperature control system of internal combustion engine
Assignee: Nissan Motor Co Ltd
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Filing: 1983-12-05
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Granted: 1985-12-24
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Expires: 2003-12-05
Abstract
Abstract A coolant temperature control system of an internal combustion engine is composed of a thermostat disposed in a coolant passageway leading to a radiator. The thermostat is operatively connected to a diaphragm actuator so that valve opening temperature of a thermostat valve is controlled in response to engine loads. Additionally, the thermostat valve is arranged to be opened in response to the discharge pressure of a coolant pump, thereby lowering the opening temperature of the thermostat valve at a high speed engine operating range.
Inventors
- 👤 Shinichi Nagumo
- 👤 Yoshifumi Hase
- 👤 Fumio Sanezawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:26
CPC Classifications
F; F01; F01P; F01P7/00; F01P7/14; F01P7/16; F01P7/167; G; G05; G05D; G05D23/00; G05D23/01; G05D23/02; G05D23/021; G05D23/022; F01P2070/00; F01P2070/06
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
192 words
A coolant temperature control system of an internal combustion engine, comprising: a thermostat valve means disposed in a coolant passageway leading to a radiator and including a thermally responsive member which is movable in response to the temperature of a engine coolant flowing through the coolant passageway, a valve seat, and a movable valve member associated with said thermally responsive member and capable of operating in accordance with the movement of said thermally responsive member, said thermostat valve means being closable to block the coolant passageway so as to prevent the flow of said coolant to the radiator when said temperature of said engine coolant is below a thermostat valve opening temperature; means for increasing the value of said thermostat valve opening temperature when said engine operates in a low load engine operating range over the value of said thermostat valve opening temperature when said engine operates in a high load engine operating range; and pressure-responsive means connected to said valve seat or said valve member for driving said thermostat valve means in a direction to open in response to the discharge pressure of a coolant pump disposed in the coolant passageway.
Claim 2
Dependent Claim
192 words
A coolant temperature control system of an internal combustion engine, comprising: a thermostat valve means disposed in a coolant passageway leading to a radiator and including a thermally responsive member which is movable in response to the temperature of a engine coolant flowing through the coolant passageway, a valve seat, and a movable valve member associated with said thermally responsive member and capable of operating in accordance with the movement of said thermally responsive member, said thermostat valve means being closable to block the coolant passageway so as to prevent the flow of said coolant to the radiator when said temperature of said engine coolant is below a thermostat valve opening temperature; means for increasing the value of said thermostat valve opening temperature when said engine operates in a low load engine operating range over the value of said thermostat valve opening temperature when said engine operates in a high load engine operating range; and pressure-responsive means connected to said valve seat or said valve member for driving said thermostat valve means in a direction to open in response to the discharge pressure of a coolant pump disposed in the coolant passageway.
Claim 3
Dependent Claim
44 words
A coolant temperature control system as claimed in claim 1, wherein said valve increasing means includes a diaphragm actuator having a first diaphragm which defines a vacuum chamber evacuated by the intake vacuum of the engine, and a control member connected to said diaphragm.
Claim 4
Dependent Claim
26 words
A coolant temperature control system as claimed in claim 2, wherein said thermally responsive member includes a piston rod extendable in response to the coolant temperature.
Claim 5
Dependent Claim
34 words
A coolant temperature control system as claimed in claim 3, wherein said valve member is secured to said thermally responsive member so as to move with said thermally responsive member as a single member.
Claim 6
Dependent Claim
16 words
A coolant temperature control system as claimed in claim 4, wherein said valve seat is stationary.
Claim 7
Dependent Claim
42 words
A coolant temperature control system as claimed in claim 5, wherein said driving means includes means for urging said thermally responsive member in a direction that said valve member separates from said valve seat in response to the coolant pump discharge pressure.
Claim 8
Dependent Claim
59 words
A coolant temperature control system as claimed in claim 6, wherein said urging means includes a second diaphragm defining a coolant pressure chamber to which the coolant pump discharge pressure is led, said second diaphragm being associated with said thermally responsive member piston rod so as to push said piston rod in response to the coolant pump discharge pressure.
Claim 9
Dependent Claim
32 words
A coolant temperature control system as claimed in claim 7, wherein said second diaphragm is secured to said diaphragm actuator control member which is contactable with said thermally responsive member piston rod.
Claim 10
Dependent Claim
36 words
A coolant temperature control system as claimed in claim 8, wherein said thermostat includes a first spring for urging said valve member in a direction to cause said valve member to contact with said valve seat.
Claim 11
Dependent Claim
43 words
A coolant temperature control system as claimed in claim 9, wherein said diaphragm actuator includes a second spring disposed in the vacuum chamber to urge said first diaphragm in a direction that said control member moves toward said thermally responsive member piston rod.
Claim 12
Dependent Claim
52 words
A coolant temperature control system as claimed in claim 10, wherein the locational relationship between said valve member and said valve seat of said thermostat is such that the coolant pump discharge pressure acts on said valve member to urge said valve member in a direction to contact with said valve seat.
Claim 13
Dependent Claim
52 words
A coolant temperature control system as claimed in claim 5, wherein the locational relationship between said valve member and said valve seat of said thermostat is such that the coolant pump discharge pressure acts on said valve member in a direction to urge said valve member to separate from said valve seat.
Claim 14
Dependent Claim
29 words
A coolant temperature control system as claimed in claim 12, wherein said thermostat is disposed in said coolant passageway upstream of the coolant pump and downstream of the radiator.
Claim 15
Dependent Claim
63 words
A coolant temperature control system as claimed in claim 4, wherein said driving means includes a connecting member for rigidly connecting said thermostat valve seat with said diaphragm actuator control member, and a bellows connected to said valve seat and arranged to receive the coolant pump discharge pressure so that said valve seat is movable in response to the coolant pump discharge pressure.
Claim 16
Dependent Claim
23 words
A coolant temperature control system as claimed in claim 14, wherein said thermally responsive member piston rod is secured to a stationary member.
Claim 17
Dependent Claim
29 words
A coolant temperature control system as claimed in claim 14, wherein said thermostat is disposed in said coolant passageway upstream of the radiator and downstream of the coolant pump.
Claim 18
Dependent Claim
58 words
A coolant temperature control system as claimed in claim 3, wherein said driving means includes means for allowing said thermostat valve seat to be movable in the axial direction of said thermally responsive member in response to the discharge pressure of the coolant pump, and means for rigidly connecting said valve seat with said diaphragm actuator control member.
Claim 19
Dependent Claim
26 words
A coolant temperature control system as claimed in claim 17, wherein said thermostat valve member is movable in the axial direction of said thermally responsive member.
Claim 20
Dependent Claim
23 words
A coolant temperature control system as claimed in claim 18, wherein said thermally responsive member piston rod is fixed to a stationary member.
Claim 21
Dependent Claim
35 words
A coolant temperature control system as claimed in claim 1, wherein the discharge pressure of said coolant pump is higher in a high engine speed operating range than in a low engine speed operating range.
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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) | 1988-12-23 | 1989-06-24 | 1989-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-23 | 1993-06-24 | 1993-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-23 | 1997-06-24 | 1997-12-24 | $7700.00 | Window Closed / Lapsed |