JPS6147975B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel supply system, particularly in a conventional carburetor for an automobile engine, in which gasoline and air are drawn into the carburetor and mixed in a suitable proportion for distribution to the engine. . In this device, it is desired that the gasoline fuel be completely vaporized and mixed with air to ensure maximum fuel efficiency and to avoid releasing unburned hydrocarbons that pollute the atmosphere at the exhaust of the engine. but,
When the engine is operated in a cold environment and starts cold, it is difficult to achieve complete fuel vaporization using a conventional vaporizer. That is, when the temperatures of the air and fuel drawn into the carburetor are low and the engine itself is still at a low temperature, complete fuel vaporization may not necessarily be achieved and the air-fuel mixture distributed to the engine may be unvaporized. They tend to contain droplets of fuel. In this regard, conventional carburetors are designed to provide a superfueled air-fuel mixture under such operating conditions to facilitate starting of the engine motor, which reduces the amount of unvaporized fuel in the air-fuel mixture. This will result in an increase. Attempts have been made to preheat the air-fuel mixture distributed in automobile engines, but these attempts are not effective enough to transfer heat to the air-fuel mixture and often fail to reach full operation after the engine has been started. It doesn't necessarily make it possible.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved carburetor for a motor vehicle engine, to provide a vaporizer which achieves improved mixing and vaporization of fuel and air for the distribution of a motor vehicle engine. - To provide an improved apparatus for efficiently and effectively heating an air-fuel mixture to achieve improved fuel vaporization prior to dispensing the fuel mixture, heating the air-fuel mixture immediately after starting the engine; The object of the present invention is to provide a device which operates to do the following: a carburetor device which is easy and economical to manufacture and which can be used in conventional automobile engines.

It is another object of the present invention to provide an improved system that can operate without unduly restricting the flow of air-fuel mixture to the engine; The present invention provides an apparatus which is simple, compact, reduces pollution-causing gas emissions and is fuel efficient when starting an engine from cold; The purpose of the present invention is to provide a device with a simple and inexpensive structure.

In summary, the new and improved vaporizer of the present invention provides an air-fuel passage and an air inlet to the passage; a fuel inlet of the passage for mixing fuel and air in the air-fuel passage; It includes a conventional carburetor with an air-fuel passage outlet for dispensing the vaporized fuel mixture. A heater device having a body of a ceramic material with a positive temperature coefficient of resistivity has a device for conducting electrical current through the body and a vaporizer for passing an air-fuel mixture from the heater passageway in heat transfer relation to the heater body. The body of ceramic material has a plurality of passageways extending therethrough. In accordance with the present invention, the heater body has a relatively small number of passages of relatively large cross section to confine a very thin web of resistor material between the passages, thereby directing the air-fuel mixture to the engine. on the resistor body along the inner wall of the resistor body passage to provide a large effective ohmic contact area for the resistor material to pass through the resistor body quickly from the heater passage without unduly impairing the flow of the air-fuel mixture. An ohmic contact is placed at. The ohmic contact formed in the wall of one body passage is preferably formed in one body end and with a first coating of electrically conductive material extending around the side of the body near the one body end. Thus, they are electrically connected together at one end of the main body. The ohmic contact in the other body passage is
The bodies are electrically coupled together at the opposite ends by a second coating of electrically conductive material on the opposite body ends that extends around the sides of the body near the opposite body ends.
The resistor body is held within a housing of rigid electrically insulating material having a hole on its opposite side aligned with the heater passageway. The housing also has mounting holes for holding the heater between the carburetor and intake manifold of the automobile engine. A pair of generally scalloped annular terminals are retained in a housing extending around the resistor body in resilient engagement with first and second coverings on each side of the resistor body, each terminal being attached to a motor vehicle. It has one section extending outside the housing to be connected to a 12 volt power source. The heater device is arranged to be energized when engine operation is started and effectively deenergized thereafter when the engine has warmed to its optimal operating temperature.

In this arrangement, the carburetor does not unduly restrict the flow of air-fuel mixture to the engine. However, an automobile's 12 volt power supply is effective in directing significant current from a thin web of resistor body material between ohmic contacts of different magnetic poles formed nearby within the body passageway. By this method, the heater system of the vaporizer generates a large amount of heat with the electrical power available to heat the air-fuel mixture through the heater passages to effect vaporization of the fuel within the mixture. Additionally, the heater used in the carburetor is compact, durable, and inexpensive and can be used in conventional carburetors without unduly increasing the height of the carburetor of an automobile engine.

Embodiments of the present invention will be described below with reference to the drawings. Code 1 in Figures 1 and 2
0 indicates an efficient vaporization device of the present invention, which device includes an air-fuel passage 14, an air inlet 16 to the air-fuel passage, and an air-fuel passage to the air-fuel passage for mixing fuel and air in the air-fuel passage. It has a carburetor 12 of the conventional type having a fuel inlet 18 and an air-fuel passage outlet 20 for distributing a mixture of air and vaporized fuel to a motor vehicle engine 22. Such a conventional vaporizer has a bench lily portion 2 as shown in FIG.
Body 2 defining an air-fuel passage 14 with 6
4, chiyoke valve device 28, throttle valve device 30,
and a gasoline fuel 3 as schematically shown in FIG.
It has a supply chamber 32 for 4. A typical carburetor has an opening 40 to the intake manifold passage 42 leading to the engine cylinder and the carburetor air-fuel passage 14 aligned for use in holding the carburetor against the engine's intake manifold 38. It has a flange 36. In normal carburetor operation, the negative pressure created in the intake manifold when the engine is running is
While drawing air into the carburetor inlet 16 as shown at 4, the reduced pressure created in the ventilator restraint in the air-fuel passage draws fuel from the jet or nozzle inlet 18 as shown at arrow 46, thereby A mixture of air and vaporized fuel is created in the air-fuel passage as shown at 48. The air-fuel mixture 48 is then drawn from the air-fuel passage outlet 20 into the intake manifold as indicated by arrow 50 and distributed to the engine as shown in FIGS. 1 and 2. In a conventional carburetor, the throttle valve is actuated and controlled by a suitable linkage to regulate the amount of air-fuel mixture distributed to the engine, and the choke 26 regulates the supply of air to the carburetor. The intake manifold is actuated in response to negative pressure suction and a thermally responsive spring device. The carburetor 12 is of a conventional type and will not be described in detail here.The efficient carburetor of the present invention is simple and suitable for supplying air-fuel mixtures to double or quadruple barrel carburetors or automobile engines. It can be seen that it is used in other fuel supply devices.

In this regard, when the automobile engine is started from cold, especially in cold environmental conditions, the carburetor 12
The air 44 and fuel 46 drawn into the carburetor are at too low a temperature to result in complete vaporization of the fuel within the carburetor air-fuel passage.
Additionally, the temperature of the engine 22 may be too low for a period of time after startup to heat the air-fuel mixture 48 sufficiently to effect complete vaporization of the fuel within the mixture. In a conventional carburetor, the choke 26 restricts the air supply to the carburetor during engine startup or warm-up, thereby ensuring that the air-fuel mixture distributed to the engine provides smooth engine starting. The fuel is getting richer. As a result, under these start-up conditions, the air-fuel mixture 48 includes fuel droplets 52 or degassed fuel as shown in FIG.
Therefore, the engine has relatively low fuel efficiency during startup and, more importantly, unburned hydrocarbon contaminants tend to be emitted to the atmosphere from the engine exhaust during motor startup.

Thus, in the carburetor 10 of the present invention, the heater device 54 is connected to the carburetor 1 to heat the air-fuel mixture 48 being distributed to the engine.
2 and the intake manifold 38, thereby allowing significantly improved vaporization of the fuel component of the air-fuel mixture prior to dispensing the mixture to the engine. In order to achieve this improved fuel vaporization without unduly restricting the free flow of the air-fuel mixture to the engine, a more efficient power source useful for this purpose is derived from the 12 volt vehicle power source. It is necessary to use it often.
Accordingly, the heater device used in the vaporizer 10 of the present invention includes a heater body 56, such as a positive temperature coefficient of resistivity (PTC) ceramic material, with a resistor between adjacent passages of the body. Both ends 56.1 of the body to define a thin web 59 of material
and a plurality of passageways 58 extending from the body between 56 and 2 in a spaced pattern aligned with each other.
has.

As shown in FIG. 2, the resistor material joint 60
is formed around the edge of the end of one of the body passageways 58a, while a similar joint 62 is formed around the end of the other body passageway 58b. Electrically conductive ohmic contacts 64 are attached to the resistor body along the inner wall of each passageway 58. The ohmic contact 64 in said other body passage 58b includes a coating 66 of electrically conductive material deposited over the entire body end 56.1 so as to extend around the side of the joint 60.
are electrically connected to each other at the main body end 56.1. A coating 66 of electrically conductive material is in electrical contact with the ohmic contact 64 in the passageway 58b, but is spaced from the ohmic contact 64 in the body passageway 58a by the top of the joint 60. Similarly, the ohmic contacts 64 in every other body passageway 58a are coated with electrically conductive material deposited over the opposite end 56, 2 of the body so as to extend around the sides of the joint 62. They are electrically connected to each other at the opposite ends 56, 2 by means of an object 68. The overall relationship between the ohmic contact portions of the passages in each group and the coating covering the end of the main body is shown in FIG.
It will be particularly well understood. These coatings 66,
68 is made of the same electrically conductive material used to form ohmic contact 64, as seen in FIG. Each of the coverings 66 and 68 has a covering portion 66.1 and 68.1 extending circumferentially around the side of the resistor body proximate each end of the body. Preferably, the covering portions 66.1 and 6
8.1 is further coated with an electrically conductive material exhibiting a relatively low electrical sheet and surface contact resistance. This condition is indicated at 69 in FIG. A protective coating 71 is also applied to the resistor body between coating portions 66.1 and 68.1.

For example, resistor body 56 is typically made from a lanthanum-treated barium titanate ceramic resistor material that has a positive temperature coefficient of resistivity and exhibits a sharp, abnormal increase in resistivity when heated to a selected temperature. Become. Preferably, for example, the body is about
Room temperature resistivity of 36 ohm cm and approx.
Empirical formula Ba ₀ . ₉₆₈ Pb ₀ . with a Cuyuri temperature of 140 °C.
₀₃₀ La ₀ . ₀₀₂ Consists of ceramic titanate represented by TiO ₃ . It also exhibits a sharp abnormal resistivity increase of about 10 ⁵ ohm centimeters when heated above an abnormal temperature of about 200°C.

In the vaporizer 10 of the present invention, the resistor body 5
The six passageways 58 preferably each have a square cross-section and relatively large cross-sectional dimensions on the order of at least about 0.100 inch on the sides. The web of resistor material 59 between the body passages also has a thickness of approximately
It is made relatively thin, on the order of 0.060 inches or less. Typically, for example, the passageways 58 are approximately
Spaced from the adjacent body passages by a web 59 of resistor material, each quadrilateral cross-section of 0.140 inches and about 0.040 inches thick, the body has eight rows of such passages, one for each passage. has eight passages arranged in rows. Preferably, resistor body 56 has an overall thickness of about 0.250 inches so that each passageway 58 has a length of about this dimension.

In the vaporizer 10 of the present invention, the resistor body 56 is preferably held relative to the vaporizer 12 such that the resistor body passageway is in heat transfer relationship to the body 56.
8 to air - air to pass through the fuel mixture 48 -
It becomes aligned with the fuel passage 14. The configuration of the resistor body 56 as described above allows the body to act as a highly efficient fluid heater and allows the heater body to operate even at very low voltages, such as the 12 volt power supplies useful in automobiles. It is adapted to provide a large amount of heat to the air-fuel mixture 48 even when energized. That is, the resistor body end sheathings 66 and 68 are connected to the appropriate terminals and current is directed through each of the resistor material webs 59 disposed between adjacent body passageways 58. This current flows between one group of ohmic contacts 64 of one electrode attached to sheath 66 and another group of ohmic contacts of the opposite electrode attached to sheath 68. In this manner, the plurality of ohmic contacts in the body passage cooperate to provide a large effective area of ohmic contact to the resistor material. On the other hand, because the web 59 between the body passages is thin, even when a relatively low voltage is applied across the ohmic contacts of the opposite electrode, it is difficult to pass the thin web against each unit area of the ohmic contacts. Relatively large currents can then be conducted. Furthermore, even though a resistivity gradient occurs within the resistor body between the ends of the body as a result of the flow of the air-fuel mixture 48 through the body passages, the occurrence of high resistivity in the body adjacent to one body end is does not limit heat generation to the other part of the body. Therefore, even though passageway 58 is relatively large to allow flow of air-fuel mixture from the passageway without significant restriction, a large amount of heat is efficiently generated by the resistor body. and is transferred to the air-fuel mixture to efficiently heat the air-fuel mixture.

For example, resistor body 56 may have a thickness of 0.25 inches and eight of the eight passages each extending through the body.
If the main body has a row of As shown in FIG.
It is adapted to pass a significant amount of air-fuel mixture through the air-fuel mixture. That is, the body passes a significant amount of air-fuel mixture with only a small pressure drop across the body, as shown by curve 70 in FIG. For example, during operation of the automobile engine 22, 5 pounds of air-fuel mixture per minute (69.25 cubic feet of air-fuel mixture per minute) is directed through the first stage of the double-barrel carburetor into the heater body passages. This flow causes a pressure drop of only 12 centimeters (0.15 pounds per square inch) of water across the body of the resistor. However, when energized by the 12 volt vehicle power supply, the heater body generates a significant amount of heat, as shown by curve 72 in FIG.
That is, when 5 pounds per minute of air-fuel mixture is directed from the body passages, heater body 56 generates and transfers 400 watts of energy to the air-fuel mixture. This heat transfer increases the temperature of the air-fuel mixture by about 12° and significantly improves the vaporization of the fuel component of the mixture when the air and fuel components are introduced into the vaporizer 12 at relatively low temperatures. It is effective for Of course, the heater body is adapted to begin heating the air-fuel mixture immediately after starting the motor, and thus to provide improved fuel vaporization when necessary, before the engine itself has warmed up to any appreciable degree. It's getting old. Additionally, the positive temperature coefficient of resistivity of the resistor body material ensures that the heater body is self-regulating. That is,
As the temperature of the body increases, the resistivity of the body also increases, reducing the level of current flowing through the body, so that the body temperature stabilizes at a safe temperature and the heat generated in the body at that temperature is transferred to the body. It is designed to balance the heat dissipated from the It will be appreciated that the heater system is adapted to very efficiently heat the air-fuel mixture 48 from a low voltage power source without restricting the flow of the air-fuel mixture from the heater body passages.

Preferably, the compact resistor body 56 includes:
A body of positive temperature coefficient resistivity resistor material is provided, the body having a plurality of resistor materials extending between its ends in a pattern in side-by-side spaced relation through the body and between the passages. having a plurality of passageways defining a web of the body and having an abutment of resistor material extending around each end of every other passageway at one end of the body and as described above at the other end of the body. and an abutment of resistor material extending around each end of the other passageway. The inner wall of the passageway is then coated with an electrically conductive material in ohmic contact with the resistor material, and one end of the body is coated with an electrically conductive material around the abutment at said one end and the other end is coated with an electrically conductive material at said one end. ohmic contact coatings in the passageways are electrically interconnected and said other end is coated with an electrically conductive material around an abutment at said other end in said other passageway; Electrically interconnecting the ohmic contact coverings.

In the vaporizer 10 of the present invention, the heater device 5
4 also preferably includes a housing arrangement 74 for conveniently retaining resistor body 56 between carburetor 12 and intake manifold 38 without unduly increasing the height of the carburetor. A spacer 76, preferably made of a rigid electrically insulating material such as phenolic resin, has a central opening 78 mounted around the resistor body 56. A pair of generally corrugated annular terminals 80 are constructed of an electrically conductive spring material, such as beryllium copper, and are mounted around the sides of the resistor body proximate each end of the body, thereby lowering the Contact resistance coating 69 and coating portion 6
6.1 and 68.1. In this device, the terminals 80 are in multi-point pressure contact with the low resistance coating 69, and the terminals are separated from each other by spacers 76. Each terminal 80 has a terminal portion 80.1 extending laterally therefrom, particularly as shown in FIG. The two outer housing portions 82, 84 are preferably comprised of phenolic resin and each have a hole 86 and a recess 88 therein.
A recess 88 is mounted over the end of the resistor such that the hole 86 is aligned with the resistor body passageway 58. Preferably, each of the outer housings 82, 84 is centered on or attached in sealing relation to one side of the spacer 76 and the housing portion and spacer connect the heater device 54 to the carburetor 12 and intake manifold 38. Attachment holes 90 are provided for use in retaining. The device 10 preferably includes a device for sealing the housing device to the vaporizer. Each housing part has a groove 91 that allows one of the terminal extensions 80.1 to extend outside the housing 74. Preferably, a gasket 92 of compressible material with an opening 54 therein is enclosed between each housing portion and the resistor body 56 to prevent damage to the ceramic body when subjected to vibrations, shocks, etc. This arrangement ensures that the ceramic resistor body is located within the housing 74. Preferably, a screen material 96 of non-conductive material, such as fiberglass, is enclosed within the housing at the exit end of the housing 74 between the resistor body 56 and the housing portion 84 to prevent small debris from the ceramic resistor body. engine 2
2. Prevents it from entering. Preferably, a similar screen 98 is also surrounded by the housing between the resistor body 56 and the housing portion 82;
Fuel droplets 52 entering the body passageway are dispersed to facilitate vaporization of the droplets.

Due to the structure of the heater device 54 as described above,
The heater device is conveniently held between the carburetor 12 and the intake manifold 38 by using mounting screws 99. The terminal portion 80.1 of the heater device is easily connected to a vehicle's 12 volt power supply or the like by power terminals 100 and 102, as shown in FIG. Preferably, heater device 4 is adapted to be energized when ignition switch 104 is closed to start engine 22, as shown in FIG. Similarly, the control device 106 has a heater device 54 inserted in series with the engine 2.
2 reaches its sufficient operating temperature and the heater device 5
4 is no longer required, the output of the heater device is reduced or the heater device is deenergized for a period of time after motor start-up. Such control device 106 may include a conventional time delay device, a thermostatic device activated in response to the temperature of engine 22, or any other suitable conventional control device.

Although the present invention has been described above with reference to the drawings, various modifications and changes can be made to the present invention within the scope of the invention as set forth in the claims.

[Brief explanation of the drawing]

1 is a sectional view taken along the longitudinal axis of the improved vaporizer of the present invention; FIG. 2 is an enlarged sectional view of a heater device used in the apparatus shown in FIG. 1; and FIG. Figures 4 and 5 are relatively small and reduced cutaway views of the heater device used in the device.
FIG. 2 is a graphical representation of the operating characteristics of the device shown in the figure; 12... Carburetor, 14... Air-fuel passage, 1
6...Air inlet, 18...Fuel inlet, 22...Engine, 24...Main body, 54...Heater device, 5
6... Heater main body, 58... Main body passage.

Claims (1)

[Claims] 1 an air-fuel passageway and an air inlet to the passageway;
A fuel inlet that allows fuel to be mixed with air into the passageway, an outlet that allows the air and fuel mixture to exit the passageway, and a rapid increase in electrical resistivity when heated to a selected temperature to stabilize at a safe temperature. and a heater device of a ceramic resistor material of positive temperature coefficient resistivity which exhibits a significant increase in resistivity;
A fuel supply device in which the heater device is configured to heat an air-fuel mixture, wherein the heater device has a plurality of heater body passages in side-by-side spaced relation between opposite ends of the heater body, each a heater body of positive temperature coefficient resistivity resistor material defining a thin web of resistor material between the heater body passage and each adjacent heater body passage; and a heater body passage provided on an inner wall of the heater body passage. a first electrically conductive coating on one end of the heater body electrically interconnecting every other heater body passageway, and a second electrically conductive coating on the other end of the heater body electrically interconnecting at another heater body passageway; a device for connecting the heater body to the vehicle power source for passing a current through the heater body;
and a device for attaching a heater body for passing the fuel mixture and vaporizing the fuel component of the air-fuel mixture.