Vaporizer/Carburetor and Method

The invention resides in the general field of vaporizing liquid petroleum fuel for internal combustion engines, the most common example of which is in the case of automobiles.

A broad object of the invention is to provide apparatus and method in connection therewith, for vaporizing fuel, forming a complete and unified unit specially adapted for application to an engine, without requirement for predesigning the engine for that purpose.

Another object is to provide the foregoing apparatus, having the following features and advantages:

1. It includes a novel vaporizer unit especially effective for performing the vaporizing step.

2. It maintains the temperature of the vapor produced at such level as to provide most efficient combustion.

3. It provides a vaporizing step and produces the vapor in such quantity as to provide sufficient fuel for the engine in all instances, such as and particularly at high speeds and in climbing hills.

4. The apparatus is extremely simple in manufacture and in applying it to the engine, and effective in utilizing the facilities of the engine in the operation thereof.

In the drawings,

FIG. 1 is a diagrammatic view of the engine of an automobile and related components, and the apparatus of the present invention applied thereto;

FIG. 2 is a vertical longitudinal sectional view of the vaporizer unit of the invention, oriented according to FIG. 1;

FIG. 3 is a view taken at line 3--3 of FIG. 2;

FIG. 4 is a view taken at line 4--4 of FIG. 3;

FIG. 5 is a semi-diagrammatic top view of the automobile engine and the fuel intake through the air cleaner, and related elements;

FIG. 6 is a longitudinal sectional view of a vapor tube electric heater included in FIG. 5;

FIG. 7 is a diagrammatic view of an arrangement for controlling the temperature of the vapor; and

FIG. 8 is a semi-diagrammatic view of an automatic choke for controlling the flow of vapor to the main carburetor.

FIG. 9 is a sectional view of an alternate form of vaporizer unit.

FIG. 10 is an end view taken from the left of FIG. 9.

FIG. 11 is a semi diagrammatic view, oriented according to FIG. 10, showing a different number of tubes.

FIG. 12 is a view similar to FIG. 11, showing a still different arrangement.

FIG. 13 is an end view of a tube in the vaporizer unit.

FIG. 14 shows an alternate form of feed of the vapor to the engine.

Referring in detail to the accompanying drawings, attention is directed first to FIG. 1 where the automobile engine is indicated at 10, having the usual radiator 12 included in a coolant system including fluid lines i4, 16, and the usual cooling fan 18.

The engine 10 includes an intake manifold 20 in which the vacuum is developed and sensed for performing certain operations referred to hereinbelow. The engine includes a main carburetor 22 and the usual fuel tank 24 from which the fuel is drawn through a main fuel line 26 in which is a fuel pump 28. The main fuel line 26 continues to a two-way valve 30 and from this valve leads a first branch fuel line 32 leading to the main carburetor 22, and a second branch fuel line 34 leading to the vaporizer unit 36, this unit constituting a principal component of the invention. The valve 30 as will be explained hereinbelow is operative for directing the fuel selectively through the branch lines 32, 34 and thus to the main carburetor 22 and the vaporizer unit 36 respectively in accordance with a certain sequence of operations referred hereinbelow. The vaporizer unit 36 includes an auxiliary carburetor 38 into which the second branch fuel line 34 leads. A vapor outlet line 40 leads from the vaporizer unit 36 to the main carburetor 22.

The engine 10 includes the usual exhaust pipe 42 in which a muffler 44 is included, and an exit tail pipe 46. A branch exhaust pipe 48 leads from the main exhaust pipe 42 at a juncture 50, leading to the vaporizer unit 36.

Attention is next directed to FIGS. 2, 3 and 4 showing the details of the vaporizer unit 36. The vaporizer unit includes an outer casing or shell 52 having a main chamber 54 therein, divided into two end chambers 54a and 54b by a tube structure 56 which includes a plurality of tubes 58, in this case six, leading between the chambers 54a, 54b. These tubes are mounted in end plates 60 which enclose the space 62 surrounding the tubes. The two end spaces 54a, 54b, and the tubes, constitute a longitudinal fuel passage through the unit, and the space 62 constitutes a transverse exhaust gas passage through the unit. The exhaust gases in that exhaust passage are in heat transfer relation to the tubes, for heating the fuel passing through the tubes, and vaporizing the fuel.

Preferably mesh elements 64 are placed in the tubes 58 these mesh elements being for example screen wire rolled into spirals and fitted into the tubes. The mesh units provide substantial open space for the fuel to pass therethrough, but the elements of the mesh also provide a great surface area for the particles of the atomized fuel to engage, greatly assisting the vaporization of the fuel. The fuel stream at this location is a mixture of atomized liquid fuel mixed in and carried by an air stream, produced by the auxiliary carburetor 38, and the engagement of the fuel particles with the elements of the screen mesh provide a dwell in the passage of the fuel therethrough, with greater effectiveness in vaporizing it. The vaporizer unit 36 normally assumes a position adjacent the horizontal, in the normal operation of the automobile, despite travel on inclines and the structure is such that the tubes 58 are inclined downwardly in direction opposite the direction of flow of fuel. In this instance (FIG. 2) the fuel flows generally from left to right, and the left ends of the tubes are lower than the right ends, enabling any liquid fuel that has not been vaporized to flow back, to be picked up by following increments of the air stream.

The auxiliary carburetor 38 of FIG. 2 is of known and standard type, operably associated with an air cleaner 68. The second branch fuel line 34 leads into a chamber 70 of the carburetor, from which the fuel then flows in atomized form through a nozzle 72 in the air passage 74 of the carburetor. A throttle body 76 is provided in the carburetor and manually set to a desired position, by means of a cable 77 having a manual knob 79 on the dashboard.

An electric crystal 78 is mounted at the inlet from the carburetor, for vaporizing the heavy ends of the fuel, vibrating at a frequency of in the neighborhood of one million vibrations per second. This crystal is actuated by a 12 volt current, provided by the usual battery of the automobile.

The auxiliary carburetor 38 shown in FIGS. 1 and 2 has a vertical outlet, and is positioned on top of the vaporizer unit, but a side outlet carburetor may be utilized instead, such as the carburetor 80 of FIG. 3, having an outlet leading into the chamber 54a. In the construction of the vaporizer unit of FIG. 3, cross vanes 82 (FIG. 4) are placed in the space 54a for directing the fuel more effectively into the tubes 56. In FIG. 3 also, the electric crystal 78 is utilized. FIG. 3 is a horizontal transverse sectional view and shows the branch exhaust line 48 (FIG. 1) connected to a manifold 84 which leads into the transverse exhaust passage 62, and leading from the latter is an outlet pipe 86 which may be provided with a muffler 88 and leading to the exterior at 90. FIG. 3 also shows the outlet vapor tube 40 which leads from the chamber 54b to the main carburetor 22.

A temperature sensing element 92 is positioned in the outlet pipe 86 and another temperature sensing element 94 is positioned in the vapor outlet pipe 48, and a flapper exhaust control 95 is provided in the exhaust line 86, and moved by a lever 96, as referred to hereinbelow, these elements being utilized for controlling the temperature of the exhaust vapor. The two-way valve 30 (FIG. 1) includes a solenoid 97 for actuating it, this controlled through the sensing element 92 in a known manner, directing the fuel to the vaporizer unit upon the exhaust gases reaching a predetermined temperature. If desired, the valve may be controlled manually by a Boden cable 99 (FIG. 1) having a knob 101 at the dashboard.

FIGS. 5 and 6 show an optional vapor tube heater 98, for use in such as winter climates, for providing additional heat to the vaporized fuel, being placed in the vapor outlet line 40 between the vaporizer unit and the main carburetor 22. It includes an outer tubular casing 100 and a resistance heater element 102 therein, in an electrical circuit which includes a ground 104 and a thermostat 106. A temperature sensing element o probe 108 is positioned in the unit for sensing the temperature of the fuel vapor therein and connected with a temperature indicating gauge 110, the temperature gauge and thermostat being operably interconnected in a known manner, for varying the resistance of the element for controling the temperature of the resulting fuel vapor.

FIG. 5, includes the main carburetor 22 and an air cleaner 111, the latter having an air inlet tube 112. The tube 112 has a choke valve 114 for varying the flow of the inlet air therethrough, this choke valve being operated by an arm 116 to which is connected a Boden cable 118 leading to the dashboard 120 and having a manual knob 122 thereon at that location. FIG. 5 also shows means for controlling the proportioned amount of exhaust gases flowing from the main exhaust pipe 42 (FIG. 1) to the branch exhaust pipe 48. At the juncture 50 of these lines is a flapper control valve 124 actuated by a lever 126, and leading from the lever is a Boden cable 128, continuing to the dashboard 120 where it is provided with a manual knob 130. These two manually actuated components may be provided in conjunction with automatically controlled components, as will be referred to hereinbelow.

FIG. 5 also shows the temperature probe 94 (FIG. 3) in the vapor outlet line 40, and the probe 92 in the outlet exhaust pipe 86, and conductors 132, 134, leading from those probes to a two-way switch 136 on the dashboard 120, and an additional conductor 138 leading from the switch to a temperature indicating gauge 140 also on the dashboard. The operator may turn the switch to either of its two opposite positions, for observing the temperature of the vaporized fuel in the vapor outlet line 40, or the exhaust gases in the outlet pipe 86, respectively.

It is found that the best operating temperature of the vaporized gas is approximately 250.degree. F., although it may be slightly higher than that, such as between 250.degree. F. and 260.degree. F. Upon observing the temperature of the vaporized fuel, by the temperature gauge 140 (FIG. 5) the driver may adjust, if need be, the passage of the outlet flow of exhaust gases through the pipe 86 (FIG. 3) by means of the flapper valve 95. A Boden wire 142 leads from the lever of the flapper valve to the dashboard 120 where a manual knob 144 is affixed thereto.

FIG. 7 shows an arrangement for automatically controlling the temperature of the fuel vapor. This figure shows the vaporizer unit 36 including the outlet exhaust gas pipe 86. In this outlet pipe 86 is a choke control 146 biased to closed position by a tension spring 148, and it is moved in opening direction by a unit indicated in its entirety at 150. This unit includes a line 152 connected with the intake manifold 20 (FIG. 1) at 154, and in this line is a check valve 156, the line 152 leading to a vacuum unit 158. Leading from the unit 158 is an air line 160 which continues through an air control valve 162 and then to a vacuum motor 164 of known kind, having a diaphragm actuated by air pressure. Connected to the diaphragm is an actuating rod 166, itself connected with an arm 168 on the choke control valve 146. The air control valve 162 is controlled by a thermostat 169 including the sensing element 94 (FIG. 3) in the vapor outlet line 40. Upon the temperature of the vaporized gas going above or below the predetermined values, as referred to above, the air control valve 162 is opened for controlling the vacuum condition which operates the motor 164. The vacuum in the engine, through the intake manifold, is transmitted through the line 152, releasing the check valve 156, producing a vacuum in the unit 158 which maintains a vacuum, or partial vacuum, at all times. Upon transmission of the vacuum from that unit through the line 160 as controlled by the air control unit 162, the vacuum is transmitted to the motor 164 and the external air pressure actuates the diaphragm of the motor, pulling the actuating rod 166 to the right, opening the choke control, that is, in response to a high vacuum, the motor is actuated a greater amount and opens the choke control and in response to a low vacuum, the choke control 146 closes or tends to close. This action may be start/stop or gradual as desired. As the choke control is opened or closed, the pressure of the exhaust gases in the vaporizer unit 36 is reduced or increased, respectively, with consequent variation of the temperature of the fuel mixture, including the vapor therein, produced by the exhaust gases.

Attention is directed next to FIG. 8 which shows a portion of a device for automatically controlling the flow of air into the main carburetor 22 (FIG. 1). The tube or air arm 112 is provided with a second choke valve 170 for controlling the flow of air into the air cleaner which flows in the direction indicated by the arrow 172. It assumes a full open position as indicated at 170a which is adjacent the horizontal, and another position adjacent fully closed, is indicated at 170b, being limited in the latter direction by suitable means such as stop screws 174. Secured to the choke valve 170 is a lever arm 176, and secured to the latter is the actuating rod 166 of FIG. 7, of the unit 150, which is the same as that of FIG. 7. In the present case, FIG. 8, in response to high vacuum in the vacuum line 152, the choke valve is moved toward open position, and conversely, in response to low vacuum, it is moved toward closed position. The operation of the arrangement is such that as the choke 170 is moved toward closed position, the air through the air cleaner and into the main carburetor is restricted, and as a consequence, the draw on the vaporized fuel is greater. Hence this control means is effective for controlling the quantity of vaporized fuel to the engine, which is important in such cases as climbing steep hills.

The act of mixing the fuel by the auxiliary carburetor 38 may be termed a first carburetion, and that of mixing the fuel mixture from the vaporizor unit 36, with air, by the main carburetor 22, may be termed a second carburetion.

As noted above, both manual control and automatic control may be utilized for performing the same function--for example the manual control of FIG. 8, can both be utilized without interference with each other; similarly a manual control for the valve 95 (FIG. 3) for controlling the outlet exhaust vapor, and the automatic control of FIG. 7, can both be utilized for that function, without either interfering with the other.

FIGS. 9-13 show an alternate form of vaporizer unit, semi-diagrammatic form. Referring first to FIGS. 9 and 10, the vaporizer unit is indicated at 180, and includes an outer casing 182 with two vertical plates 184, 186, forming a fore chamber 188 and a rear chamber 190. Tubes 192 are mounted in the plates, arranged in parallel, communicating between the chambers 188, 190, and arranged in three vertically spaced, horizontal rows. A divider or baffle 194 divides the fore chamber into an upper sub chamber 188a and a lower sub chamber 188b, the upper sub chamber enclosing the front ends of the tubes, in the top row, and the lower sub chamber enclosing the front ends of the tubes in the two lower rows. A divider or baffle 196 divides the rear chamber into sub chambers 190a and 109b, the former enclosing the ends of the tubes in the upper two rows and the latter forming a passage between the tubes of the lower row to the vapor outlet line 198 leading to the main carburetor.

The auxiliary carburetor 200, of the side outlet type, leads at the side to the upper sub chamber 188a. The fuel mixture flows into the upper sub chamber forwardly (to the right, FIG. 9) through the tubes of the upper row, into and through the sub chamber 190a, then rearwardly through the tubes of the middle row, into and through the sub chamber 188b, and forwardly through the tubes of the lower row, and then through the sub chamber 190b and vapor outlet line 198.

The tubes 192 are preferably constructed as shown in FIG. 13, where a spiral copper insert or screw 200 is fitted in the tube. The tubes may be about 1/2" in internal diameter, and 8" long, these dimensions being examples.

The spaces between the tubes form a transverse exhaust passage 202, communicating between the engine exhaust pipe 204 and an outlet pipe 206.

This unit 180 of FIGS. 9 and 10 includes twelve tubes 192, but this number is determined by the capacity desired, such as nine in FIG. 11, or eighteen as in FIG. 12, for different sized automobiles.

FIG. 14 shows an alternate arrangement of feeding the vapor to the engine. The vapor outlet line 198 leads to the bottom of the main carburetor 22, then through the carburetor and a conduit 208 to the intake manifold 20.