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US4218406A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic choke control

Assignee: Schmelzer Corp
•
Filing: 1979-05-11
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Granted: 1980-08-19
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Expires: 1999-05-11
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Abstract

Abstract A choke control device for delaying closing of a choke valve regulated by a temperature responsive bimetal coil after an internal combustion engine is turned off by employing a heat sink which stores the latent heat of fusion or vaporization that is delivered to the heat sink after the choke is open and the engine is operating at normal temperatures and which releases the latent heat after the engine has been turned off and cools to heat the bimetal coil and delay closing movement of the choke valve.

Inventors

  • 👤 Charles A. Detweiler

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 07:12
CPC Classifications
F; F02; F02M; F02M1/00; F02M1/08; F02M1/10; F02M1/12

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 162 words
A choke control device for the carburetor of an internal combustion engine having a choke valve, the combination comprising; a bimetal coil having one end adapted to be connected to said choke valve to move said choke valve to a closed position when the temperature of said engine is low and to move said choke valve to a fully open position at a predetermined elevated temperature of said engine, heating means to heat said bimetal coil when said engine is operating, means forming a heat sink disposed in adjacent heat transfer relationship to said bimetal coil, said heat sink including a material operable to absorb latent heat to change the state of said material as a result of said predetermined elevated temperature of said engine after said choke is in said fully open position and operable to return said latent heat to said coil during cooling of said engine to resist cooling of said coil and delay closing of said choke valve.
Claim 2
Dependent Claim 162 words
A choke control device for the carburetor of an internal combustion engine having a choke valve, the combination comprising; a bimetal coil having one end adapted to be connected to said choke valve to move said choke valve to a closed position when the temperature of said engine is low and to move said choke valve to a fully open position at a predetermined elevated temperature of said engine, heating means to heat said bimetal coil when said engine is operating, means forming a heat sink disposed in adjacent heat transfer relationship to said bimetal coil, said heat sink including a material operable to absorb latent heat to change the state of said material as a result of said predetermined elevated temperature of said engine after said choke is in said fully open position and operable to return said latent heat to said coil during cooling of said engine to resist cooling of said coil and delay closing of said choke valve.
Claim 3
Dependent Claim 36 words
The combination of claim 1 wherein the state of said material when said choke valve is closed is a solid and wherein the state of said material when said choke valve is open is a liquid
Claim 4
Dependent Claim 23 words
The combination of claim 1 and further comprising heating means operable to heat said bimetal coil in proportion to engine and ambient temperature.
Claim 5
Dependent Claim 26 words
The combination of claim 3 and further comprising a source of electrical power, said heating means comprising a PTC resistor connected to said source of energy.
Claim 6
Dependent Claim 34 words
The combination of claim 4 wherein said bimetal coil has its other end connected to a stem fastened to one side of a plate and wherein said PTC unit is connected to said stem.
Claim 7
Dependent Claim 32 words
The combination of claim 4 wherein said PTC resistor is mounted on a plate at one side thereof and wherein said bimetal coil is mounted on the other side of said plate.
Claim 8
Dependent Claim 28 words
The combination of claim 4 and further comprising a NTC element in series with said PTC element to modulate operation of the latter in accordance with engine temperature.
Claim 9
Dependent Claim 29 words
The combination of claim 7 wherein said NTC element is mounted on a plate spaced from said mounting plate and wherein said heat sink is disposed between said plates.
Claim 10
Dependent Claim 17 words
The combination of claim 8 wherein said heat sink is disposed between said PTC and NTC elements.
Claim 11
Dependent Claim 33 words
The combination of claim 1 wherein said material is operative to absorb latent heat at a temperature above the temperature at which said bimetal coil moves said choke to a fully open position.
Claim 12
Dependent Claim 26 words
The combination of claim 10 when said heat sink includes porous retaining means, said material being contained by said retaining means in all of its states.
Claim 13
Dependent Claim 31 words
The combination of claim 11 wherein said retaining means is in the form of an absorbent member, said absorbent member being saturated with said material in the form of a paraffin.
Claim 14
Dependent Claim 36 words
The combination of claim 12 wherein said heat sink material begins to change state at a temperature above the temperature at which said choke valve begins to move from its open position toward its closed position.
Claim 15
Dependent Claim 34 words
The combination of claim 13 wherein said predetermined temperature is greater than but almost equal to said temperature at which said choke valve begins to move from an open position toward a closed position.

References Cited (Backward Citations)

US3092999A Cited
US3109874A Cited
US3179098A Cited
US3463140A Cited
US3536058A Cited
US3603106A Cited
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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) 1983-08-19 1984-02-18 1984-08-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-08-19 1988-02-18 1988-08-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-08-19 1992-02-18 1992-08-19 $7700.00 Window Closed / Lapsed

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