Pulse fog generator

• US 4,811,901 A
• Filed: 05/26/1987
• Issued: 03/14/1989
• Est. Priority Date: 05/26/1987
• Status: Expired due to Term

• Current Assignee: Curtis Dyna-Fog, Ltd. (Pelsis Holding UK Ltd.)
• Original Assignee: Curtis DYNA Products Corporation
• Inventors: Roudebush, Dennis A., Stevens, Robert E.
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): TRAINOR, CHRISTOPHER
• Application Number:
  US07/053,826
• Time in Patent Office: 658 Days
• Field of Search: 239/129, 239/137, 239/138, 261/DIG. 67, 261/DIG. 68, 261/DIG. 8, 417/472, 417/412, 251/73, 137/463, 43/129, 43/130
• US Class Current: 239/138
• CPC Class Codes: A01M 13/00 Fumigators; Apparatus for distributing gases poisoning or narcotising insects by vaporising an insecticide A01M1/2022
• CPC Class Codes: B01F 23/235 for making foam
• CPC Class Codes: B05B 12/06 for effecting pulsating flow nozzles, spray head or outlet with means for generating a discharge of pulsating nature B05B1/08
• CPC Class Codes: F02M 1/02 the means to facilitate starting or idling being chokes for enriching fuel-air mixture automatic chokes F02M1/08
• CPC Class Codes: F02M 1/16 Other means for enriching fuel-air mixture during starting; Priming cups; using different fuels for starting and normal operation
• CPC Class Codes: Y10S 261/08 Carburetor primers
• CPC Class Codes: Y10S 261/68 Diaphragm-controlled inlet valve

Abstract

In the preferred embodiment of the present invention, a pulse fog generator powered by a resonant intermittent combustion device having a carburetor and a combustion antechamber, includes a starting air supply system for directing a flow of starting air into the antechamber, comprising an inlet/outlet check valve mounted over the discharge opening of a bellows that is reciprocated by a connecting rod eccentrically mounted to an electric motor. A priming pump is mounted on the carburetor, and comprises a priming fuel chamber hydraulically communicating with the carburetor and a piston reciprocatable within the priming fuel chamber to draw fuel from a fuel tank into the priming fuel chamber and to discharge the fuel from the priming fuel chamber into the carburetor. An on-off control for the combustion device includes a shut-off plate, disposed over the air inlet of the carburetor, affixed to a slidably mounted plunger so that the shut-off plate can be moved between a position covering and a position displaced from the air inlet. The pulse fog generator has a pressure responsive formulation control apparatus inserted between a formulation tank and means for injecting formulation into the exhaust tube of the combustion device. The control apparatus includes a shut-off valve biased to a closed position restricting the flow of the formulation, and a diaphragm actuator including an engagement pin, extending from a pressure actuated diaphragm, adapted to engage the shut-off valve and hold the valve in an open position while the combustion device is operating.

Claims

1. A pulse fog generator including a resonant intermittent combustion device composed of a combustion chamber and an exhaust tube communicating with the combustion chamber, one end of the tube discharging gases resulting from, and discharged under pressure produced by, combustion in the combustion chamber, an antechamber, communicating with said combustion chamber for providing a fuel-air mixture to said combustion chamber, a carburetor for supplying the fuel-air mixture to the antechamber and including a central throat passage, through which intake air flows during operation of the combustion device, a spark generating system, including a power source, for igniting the fuel-air mixture in the antechamber, a tank providing a reservoir of formulation and a formulation line through which formulation flows from the tank to the exhaust tube, the pulse fog generator comprising:

electric starting air supply means, electrically connected to the power source, including;

flexible air pumping means for pumping atmosphere air into the antechamber in response to expansion and contraction of said flexible air pumping means; and

air pump driving means for driving said flexible air pumping means and including an electric motor;

priming pump means for directing a quantity of starting fuel into the carburetor, including;

a priming fuel chamber hydraulically communicating with the carburetor; and

a priming pump piston reciprocatable within said priming fuel chamber and operable to draw fuel into said priming fuel chamber, and to discharge the fuel from said priming fuel chamber into said central throat passage of the carburetor;

means for terminating the flow of air through the central throat passage of the carburetor, including;

a shut-off plate movable between a first position preventing the flow of air through the central throat passage and a second position allowing the flow of air through the central throat passage;

a plunger attached to said shut-off plate, operable to move said shut-off plate between said first and second positions;

mounting means for slidably mounting said plunger on the carburetor so that said plunger can be operated to move said shut-off plate into said first position; and

biasing means for normally biasing said shut-off plate into said second position; and

pressure responsive means, adapted to be interposed in the formulation line, for terminating the flow of formulation through the formulation line in response to a cessation in operation of the resonant intermittent combustion device.

2. The pulse fog generator according to claim 1, wherein:

said flexible air pumping means further includes;

a bellows having a discharge opening; and

check valve means mounted over said discharge opening for controlling the flow of atmosphere air into and out of said bellows;

said electric motor includes a rotatable output shaft; and

said air pump driving means further includes;

means for reciprocating said bellows with the rotation of said output shaft, said reciprocating means eccentrically mounted to said output shaft.

3. The pulse fog generator according to claim 2, wherein:

said electric motor is electrically connected to the power source in parallel with the spark generating system; and

said starting air supply means further includes a switch for making and breaking the electrical connection between the power source and each of said electric motor and the spark generating system simultaneously.

4. The pulse fog generator according to claim 1, wherein said priming pump means further includes:

a priming pump adaptor having a bore hydraulically communicating between the carburetor and said priming fuel chamber, said priming pump adaptor adapted to be received within said priming fuel chamber in press-fit engagement.

5. The pulse fog generator according to claim 1, wherein said pressure responsive means comprises:

two position valve means for obstructing flow through the formulation line having a first position in which flow through the formulation line is obstructed and a second position in which flow through the formulation line is unobstructed;

biasing means for biasing said two position valve means to said first position; and

locking means for removably restraining said two position valve in said second position in response to pressure produced by the combustion, said restraint being removed when the pressure ceases.

6. The pulse fog generator according to claim 5, wherein:

said two position valve means includes a valve stem having a locking shoulder; and

said locking means includes;

a diaphragm operable by the pressure from combustion in the antechamber and having a flexed position when subject to pressure and a relaxed position otherwise; and

a locking pin extending from said diaphragm and movable between a locking position, when said diaphragm is in said flexed position, in which said locking pin contacts said locking shoulder to hold said two position valve means in said second position, and an open position, when said diaphragm is in said relaxed position, in which said locking pin does not contact said locking shoulder.

7. A starting system for a resonant intermittent combustion device having a combustion antechamber, a fuel-air supply for supplying a fuel-air mixture to the antechamher, and a spark generating system, including a power source, for igniting the fuel-air mixture in the antechamber, the starting system comprising:

an electric motor, electrically connected to the power source, including a movable output;

flexible air pumping means, having a discharge opening, for pumping atmosphere air in response to expansion and contraction of said flexible air pumping means;

means, connected between said output and said flexible air pumping means, for expanding and contracting said flexible air pumping means as said output moves;

check valve means mounted over said discharge opening for controlling the flow of air into and out of said flexible air pumping means; and

a starting air supply conduit extending from said check valve means and opening into the antechamber to direct a flow of starting air therein,

wherein said check valve means includes;

a valve body disposed over said discharge opening having an inlet aperture and an outlet aperture; and

a check valve wafer mounted to said valve body, having an integral flexible inlet flapper valve disposed over said inlet aperture and an integral flexible outlet flapper valve disposed over said outlet aperture.

8. The starting system of claim 7, wherein:

said movable output includes a rotatable output shaft;

said flexible air pumping means includes a bellows; and

said means for expanding and contracting includes a connecting rod, eccentrically mounted at its one end to said output shaft and mounted at its other end to said bellows opposite said discharge opening, for reciprocating said bellows with the rotation of said output shaft.

9. The starting system of claim 7, wherein:

said electric motor is electrically connected to the power source in parallel with the spark generating system; and

said starting system further comprises a switch for making and breaking the electrical connection between the power source and each of said electrical motor and the spark generating system simultaneously.

10. The starting system of claim 7, wherein the fuel-air supply of the resonant intermittent combustion device further includes a carburetor having a throat passage communicating with said combustion antechamber and a fuel tank for supplying fuel to the carburetor, the starting system further comprising:

priming pump means, adapted to be mounted on the carburetor, for directing a quantity of starting fuel into the carburetor, said priming pump means including;

a priming fuel chamber hydraulically communicating with the carburetor; and

a priming pump piston reciprocated within said priming fuel chamber and operative to draw fuel from the fuel tank through the carburetor into said priming fuel chamber, and to discharge fuel from said priming fuel chamber into said throat passage of the carburetor.

11. A pulse fog generator comprising:

a resonant intermittent combustion device composed of a combustion chamber and an exhaust tube communicating with said combustion chamber, one end of said tube discharging gases resulting from, and discharged under pressure produced by, combustion in said combustion chamber;

a tank providing a reservoir of formulation;

means for injecting the formulation into said exhaust tube for dispersion into a finely divided condition;

a formulation line through which formulation flows from the tank to the means for injecting; and

pressure responsive means, interposed in said formulation line, for terminating the flow of formulation through said formulation line in response to a cessation in operation of said resonant intermittent combustion device.

12. The pulse fog generator according to claim 11, wherein said pressure responsive means comprises:

two position valve means for obstructing flow through said formulation line, having a first position in which flow through said formulation line is obstructed and a second position in which flow through said formulation line is unobstructed;

biasing means for biasing said two position valve means to said first position; and

locking means for removably restraining said two position valve in said second position in response to pressure produced by the combustion, said restraint being removed when the pressure ceases.

13. The pulse fog generator according to claim 12, wherein:

said two position valve means includes a valve stem having a locking shoulder; and

said locking means includes;

a diaphragm operable by the pressure from combustion in the antechamber and having a flexed position when subject to pressure and a relaxed position otherwise; and

a locking pin extending from said diaphragm and movable between a locking position, when said diaphragm is in said flexed position, in which said locking pin contacts said locking shoulder to hold said two position valve means in said second position, and an open position, when said diaphragm is in said relaxed position, in which said locking pin does not contact said locking shoulder.

14. The pulse fog generator according to claim 13, wherein:

said diaphragm is an inverting diaphragm; and

said locking means further includes biasing means associated with said locking pin for biasing said pin and said diaphragm to said open position.

15. A pressure responsive flow control apparatus for a pulse fog generator having a resonant intermittent combustion device composed of a combustion chamber, and an exhaust tube communicating with the combustion chamber, one and of said tube discharging gases resulting from, and discharged under pressure produced by, combustion in the combustion chamber, a tank providing a reservoir of formulation, a formulation injector for injecting the formulation into the exhaust tube, and a formulation line through which formulation flows from the tank to the formulation injector, the flow control apparatus comprising:

two position valve means, adapted to be interposed in the formulation line, for obstructing flow through the formulation line, having a first position in which flow through the formulation line is obstructed and a second position in which flow through the formulation line is unobstructed;

biasing means for biasing said two position valve means to said first position; and

locking means for removably restraining said two position valve in said second position in response to pressure produced by the combustion, said restraint being removed when the pressure ceases.

16. The pulse fog generator according to claim 15, wherein:

said two position valve means includes a valve stem having a locking shoulder; and

said locking means includes;

a diaphragm operable by the pressure from combustion in the antechamber and having a flexed position when subject to pressure and a relaxed position otherwise; and

a locking pin extending from said diaphragm and movable between a locking position, when said diaphragm is in said flexed position, in which said locking pin contact said locking shoulder to hold said two position valve means in said second position, and an open position, when said diaphragm is in said relaxed position, in which said locking pin does not contact said locking shoulder.

17. The pulse fog generator according to claim 16, wherein:

said diaphragm is an inverting diaphragm; and

said locking means further includes biasing means associated with said locking pin for biasing said pin and said diaphragm to said open position.