US3835903A

US3835903A - Apparatus for warming cooling and/or lubricating media of internal combustion engines

Info

Publication number: US3835903A
Application number: US00138520A
Authority: US
Inventors: K Masaki; H Nishimura
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1970-05-11
Filing date: 1971-04-29
Publication date: 1974-09-17
Anticipated expiration: 1991-09-17
Also published as: DE2123360B2; CA938848A; DE2123360C3; FR2091185A5; DE2123360A1; GB1297744A

Abstract

An apparatus is provided for positively warming a cooling medium and/or lubricating medium for gasoline-powered internal combustion engines of motor vehicles thereby to reduce concentrations of unburned hydrocarbons and carbon-monoxides in the engine exhaust gases emitted when the engine is running cold or being warmed up. The apparatus includes a combustor for combusting a supplied fuel into hot gases and a heat exchanging means which is in contact with portions of the cooling and/or lubricating media. The combustor is controlled by an electric control means which is responsive to a variation in the temperature of the cooling or lubricating medium so that the hot gases are produced therein when the temperature of the medium is lower than a level which is predetermined empirically in consideration of the concentrations of the unburned hydrocarbons and carbon-monoxides which would otherwise be emitted before the temperature of the cooling or lubricating media reaches a satisfactory operating temperature. The fuel to be supplied to the combustor may be a liquefied fuel gas stored in an independent container or a usual fuel supplied from a fuel circuit for the engine.

Description

United States Patent [191 Masaki et al.

1451 Sept. 17, 1974 APPARATUS FOR WARMING COOLING AND/OR LUBRICATING MEDIA OF INTERNAL COMBUSTION ENGINES [75] Inventors: Kenji Masaki, Yokosuka; Hiroshi Nishimura, Kawasaki, both of Japan [73] Assignee: Nissan Motor Company, Limited,

Yokohama City, Japan 22 Filed: Apr. 29, 1971 21 Appl. No.: 138,520

[30] Foreign Application Priority Data May 11, 1970 Japan 45-39250 [52] US. Cl. 165/23, 165/39 [51] Int. Cl B60h 3/04 [58] Field of Search 165/23, 39, 40, 26; 123/1 19 C [56] References Cited UNITED STATES PATENTS 3,355,877 12/1967 Chaffiotte 123/119 C Primary ExaminerCharles Sukalo Attorney, Agent, or FirmRobert E. Burns; Emmanuel J. Lobato; Bruce L. Adams [57] ABSTRACT An apparatus is provided for positively warming a cooling medium and/or lubricating medium for gasoline-powered internal combustion engines of motor vehicles thereby to reduce concentrations of unburned hydrocarbons and carbon-monoxides in the engine exhaust gases emitted when the engine is running cold or being warmed up. The apparatus includes a combustor for combusting a supplied fuel into hot gases and a heat exchanging means which is in contact with portions of the cooling and/or lubricating media. The combustor is controlled by an electric control means which is responsive to a variation in the temperature of the cooling or lubricating medium so that the hot gases are produced therein when the temperature of the medium is lower than a level which is predeter mined empirically in consideration of the concentrations of the unburned hydrocarbons and carbonmonoxides which would otherwise be emitted before the temperature of the cooling or lubricating media reaches a satisfactory operating temperature. The fuel to be supplied to the combustor may be a liquefied fuel gas stored in an independent container or a usual fuel supplied from a fuel circuit for the engine.

21 Claims, 10 Drawing Figures PMENIEB 3.355903 I sum 20F 8 mum sm mu 3.8%.903

sum 3 BF 8 PAIENIED 74 fi'lsassa sum 5 or a gmzmmsmmu smsaoa SHEET 7 [IF 8 Pmmmsm 7 m4 SHEEI 8 1F 8 PHI- 4 INVENTOR ATTORNEY APPARATUS FOR WARMING COOLING AND/OR LUBRICATING MEDIA OF INTERNAL COMBUSTION ENGINES This invention is generally concerned with gasolinepowered internal combustion engines and has its particular reference to an apparatus which is specifically adapted to positively warm up either or both of the cooling and the lubricating media for the internal combustionengine when the engine is running cold or being warmed up. The apparatus herein disclosed is expected to significantly contribute to reducing concentrations of unburned hydrocarbons and carbon monoxide in the engine exhaust gases so as to aid in alleviating air pollution problems resulting from the use of the gasolinepowered internal combustion engines.

Experiments with water cooled internal combustion engines have revealed that'at least three mode cycles are required of the engine before the cooling water is warmed up to about 80C, the mode cycles corresponding to a driving time period of about 7 minutes and a running distance of about 4 kilo-meters. The term mode cycle as herein used is intended to refer to a cycle of a certain driving mode of the engine such as idling, accelerating, normal cruising and decelerating modes. Thus, for instance, the three mode cycles may consist of consecutive cycles of idling, accelerating and normal cruising modes or otherwise they may be made up of successive cycles of accelerating, normal cruising and decelerating modes.

The experiments have also indicated that the concentrations of the unburned hydrocarbons and carbon monoxide contained in the engine exhaust gases are closely related to the temperature of the engine cooling water and decrease abruptly once the temperature of the cooling water has reached about 50C by which time usually the engine is driven in two mode cycles. Such concentrations become minimum when the temperature of the cooling water reaches about 80C and are maintained substantially unchanged thereafter.

Other experiments have been conducted to determine relationsbetween the concentrations of the unburned hydrocarbons and carbon monoxide and the temperature of the engine lubricating medium, revealing that such concentrations sizeably decrease as the lubricating medium becomes warmer. A low temperature of the lubricating medium is indirectly reflected by a low temperature of the cooling water and for this reason, again, the unburned hydrocarbons and carbon monoxide are emitted in relatively high concentrations before the engine lubricating medium is sufficiently warmed up.

In order that the concentrations of the unburned hydrocarbons and carbon monoxide be reduced for air pollution preventive purposes, therefore, it is advantageous to have either or both of the engine cooling and lubricating media warmed positively up to certain temperatures as early as possible after the engine has been started. Warming the engine lubricating medium, if practised, will be conducive not only to solving the vehicular air pollution problems but to enabling the engine to be lubricated satisfactorily in a significantly shortened period after the engine is started.

It is thus desirable to provide an apparatus which is capable of positively warming at least one of the cooling and the lubricating media for the gasoline-powered internal combustion engine when, and only when, the

gases, heat exchanging means communicating with the combustor and positioned substantially in contact with one or both of cooling and lubricating circuits of the engine for transferring a major portion of the heat of the hot gases therethrough, and an electric control means which is responsive to variation in the temperature of one of the engine cooling and lubricating media for actuating the combustor when the temperature of the cooling or lubricating medium is lower than a level which is predetermined in relation to the concentrations of the unburned hydrocarbons and carbon monoxide which would be emitted unless the apparatus according to this invention is installed on the engine. Valve means is interposed between the fuel source and the combustor, controlled by the electric control means so as to be open when the temperature of the cooling or lubricating medium is lower than the predetermined level which is above mentioned. The fuel to be supplied from the fuel source may be a liquefied fuel gas or a usual fuel for the engine. Where the fuel for the engine is to be utilized, the fuel source may include a fuel passage which is branched from a fuel circuit for the engine and an evaporator communicating with the fuel passage, the evaporator being supplied with the fuel from the engine fuel circuit and having heating means for heating and evaporating the supplied fuel into a combustible mixture of fuel and air. This heating means is also connected to the above-mentioned electric control means and actuated concurrently as the combustor and the valve means are actuated. Or other wise, the fuel source may include a fuel passage which, on the one hand, is vented from the open air through a restriction and, on the other hand communicates with a float chamber of the engine through another restriction whereby a combustible mixture of fuel and air is supplied therethrough. The apparatus according to this invention may further include an exhaust passage leading from the heat exchanging means for discharging an unconsumed portion of the heat in the hot gases drawn into the heat exchanging means. Such exhaust passage may preferably be positioned adjacent to an air inlet for the engine, a carburetor or an intake manifold of the engine so that air or a combustible mixture of fuel and air is warmed up when passing therethrough. Where, in particular, the engine fuel is fed to the apparatus according to this invention, the exhaust passage may be led to the intake manifold either directly or through the carburetor downstream of a carburetor throttle valvei Various embodiments of this invention are illustrated in the accompanying drawings in which like reference numerals are alotted to corresponding parts and in which:

FIG. 1 is a graph indicating variations of the temperatures of the engine cooling water and the lubricating fluid in terms of the previously defined mode cycle, time in minutes and running distance in kilo-meters;

FIG. 2 is a graph showing variations of the concentrations of the unburned hydrocarbons and carbonmonoxided in the exhaust gases from a typical conventional internal combustion engine, such variations being indicated in terms of the mode cycle, time and running distance similarly to FIG. 1;

FIGS. 3 to 9 are schematic views showing various embodiments of this invention, wherein FIG. 3 shows an apparatus adapted to warm up the engine cooling water through combustion of a liquefied fuel gas, FIG. 4 shows a modification of the apparatus of FIG. 3, FIG. 5 shows an apparatus in which the engine cooling water is warmed by combustion of the same fuel as that fed to the engine, FIG. 6 shows an apparatus intended to warm up the engine lubricating fluid through combustion of a liquefied fuel gas, FIG. 7 shows an apparatus by which the engine lubricating fluid is warmed by co mbustionof the same fuel as that fed to the engine fuel, FIG. 8 is a modification of the apparatus of FIG. 7, and FIG. 9 shows an apparatus adapted to warm up both the engine cooling water and the engine lubricating fluid through combustion of liquefied fuel gas; and

FIG. 10 is a sectional view showing, on an enlarged scale, a preferred construction of a combustor for use in the apparatus of FIG. 9.

As previously noted, the engine should be operated in at least three mode cycles and the motor vehicle should be driven for about 7 minutes and over a distance of about 4 kilo-meters before the cooling water of the engine reaches about 80C. This is clearly seen in FIG. 1, wherein the temperature of the cooling water is indicated by a curve a. The concentrations of the unburned hydrocarbons and carbon monoxide vary in close relation to the variation in the temperature of the engine cooling water, as will be understood from observation of FIG. 2 in relevance to curve a in FIG. 1. In FIG. 2, the concentrations of the hydrocarbons and carbon monoxide are indicated by curves c and d, respectively, and in terms of percentage in which 100 percent is assumed to be the lowest concentration attained when the engine is satisfactorily warmed. As seen in FIGS. 1 and 2, the concentrations of the unburned hydrocarbons and carbon monoxide decrease as the temperature of the engine cooling water increases beyond about 50C by which time the engine has been operated in about two mode cycles. As the cooling water is warmed up to about 80C, the concentrations of the unburned hydrocarbons and carbonmonoxides are reduced to a minimum and are thereafter maintained substantially constant.

The concentrations of the unburned hydrocarbons and carbon monoxide also vary in relation to the variation in the temperature of the engine lubricating fluid, the variation being indicated by a curve b in FIG. 1.

Thus, the invention proposes to reduce the concentrations of the unburned hydrocarbons and carbon monoxide by positively warming up one or both of the engine cooling water and the engine lubricating fluid so as to provide a useful solution to the vehicular air pollution problems.

A first embodiment of this invention to achieve such purpose is now illustrated in FIG. 3, wherein the shown apparatus is adapted to warm up the engine cooling water with use of a liquefied fuel gas which is isolated from the fuel circuit for the engine.

Referring to FIG. 3, the apparatus according to this invention is mounted on a usual gasoline-powered internal combustion engine which is generally represented by reference numeral 10. The internal combustion engine 10 has, as customary, an intake manifold 11 leading from a carburetor l2, and an exhaust manifold 13. The engine 10 also includes a cooling circuit 14 which is branched from the engine as at 14a and leads to a pump 14b. The engine cooling water is circulated and recirculated through this cooling circuit 14. The construction and arrangement of such cooling circuit per se is well known and, as such, detailed discussion thereof is herein omitted.

An apparatus is now provided which is adapted to warm up the cooling water in the cooling circuit 14. Such apparatus comprises a source or container 15 of a liquefied fuel gas and an injection nozzle 16 communicating with the container 15 through a fuel passage 17. The injection nozzle 16 opens into a combustor 18 having an igniter 18a and an air inlet port 18b which is shown as formed around the nozzle 16. Heat exchanging means 19 is connected to the combustor 18 and held in contact with a portion of the cooling circuit 14 intermediate between the outlet 14a and the water pump 14b. The heat exchanging means 19 communicates with an exhaust passage 20 through which an unconsumed heat in the heat exchanging means 19 is discharged therefrom. Normally closed valve means 21 which may be a solenoid actuated valve is mounted in the fuel passage 17 so as to selectively deliver the liquefied fuel gas to the injection nozzle 16 and into the combustor 18. The igniter 18a and the valve means 21 are controlled by means of an electric control circuit having a source 22 of electric power.

The electric control circuit includes, in addition to the power source 22, switch means 23 which is responsive to the variation in temperature of the engine cooling water through, for instance, a thermostat action. The switch means 23 is closed when the temperature of the cooling water is lower than a predetermined level which may be about C for the reason previously discussed with reference to FIGS. 1 and 2. The electric control circuit further includes means 21a to control the valve means 21. Where the valve means 21 is a solenoid actuated valve, the means 21a may be a solenoid coil for moving a combination armature and valve member (not shown) which may form part of the valve means 21. The igniter 18a and the means 21a are connected in parallel to each other and in series with the power source 22 and the switch means 23. An ignition switch 24 for an ignition distributor (not shown) of the ignition switch 24 for an ignition distributor (not shown) of the engine 10 may be connected between the power source 22 and the switch means 23, if preferred.

When, in operation, the engine 10 is started with the ignition switch 24 closed and when the temperature of the engine cooling water circulated through the cooling circuit 14 is lower than the previously noted predetermined level, then the switch means 23 is closed to make the electric control circuit complete, thereby energizing the valve means 21 and the igniter 18a. The valve means 21 is thus actuated to open so as to supply the liquefied fuel gas to the injection nozzle 16 through the passage 17. The fuel gas is caused to discharge into the combustor 18 through the nozzle 16 and is mixed with air sucked in through the air inlet port 18b of the combustor. At this instant, the igniter 18a is also actuated so as to fire the mixture of the fuel and air in the combustor 18, thereby producing hot gases. The hot gases are supplied to the heat exchanging means 19 through which the cooling circuit 14 passes. A major portion of the heat in the hot gases is thus transferred to the cooling water passed through the cooling circuit 14 and the warmed cooling liquid is fed to the water pump 14b. As soon as the temperature of the engine cooling liquid which is positively warmed in this manner reaches the predetermined level, the switch means 23 is opened so that the igniter 18a and the control means 21a are disconnected from the power source 22. The valve means 21 is thus closed to terminate the supply of the liquefied fuel gas and the igniter 18a is made inoperative, preventing the cooling water from over-heating.

The exhaust passage 20 may be positioned and directed in any desired manner but it is preferable that the same be positioned adjacent to an engine air inlet such as an air cleaner (not shown), the engine intake manifold 11 or the carburetor 12 whereby the hot gases discharged from the heat exchanging means 19 are used to warm the air or the combustible mixture passing therethrough.

It may be mentioned that the apparatus which is arranged in a manner above described and shown can be actuated before the engine is started insofar as the ignition switch 24 is closed. This will be beneficial for warming up the engine in a relatively short while with the engine kept at rest.

A modified form of the apparatus of FIG. 3 is now shown in FIG. 4. The apparatus herein shown is essentially similar in construction and operation to the apparatus shown in FIG. 3, installed on an internal combustion enginehaving an intake manifold 11 and a carburetor 12. Designated by reference numeral 25 is an engine air cleaner which is usually mounted on an air horn (not identified) of the carburetor 12.

The engine has a cooling circuit 26 which is branched from the engine through an outlet port 26a and led to a water pump (not shown) of the engine through an inlet port 26b. This cooling circuit 26 is essentially similar to the counterpart 14 of the arrangement of FIG. 3, serving to have the cooling water circulated and recirculated therethrough so as to cool the heated engine during operations. Different from the cooling circuit 14 of FIG. 3, the cooling circuit 26 is partly clad in a water jacket 27 which is located in the intake manifold 11 of the engine 10, as illustrated.

The engine 10 having the cooling circuit 26 thus constructed is provided with an apparatus including, similarly to the apparatus of FIG. 3 a source or container 15 of a liquid fuel gas, an injection nozzle 16 communicating with the container 15 through a fuel passage 17, and a combustor 18 into which the injection nozzle opens. The combustor 18 includes an igniter 18a and an air inlet port 18b. Normally closed valve means 21 is interposed in the fuel passage so as to selectively supply the liquefied fuel gas to the injection nozzle 16.

The combustor 18 communicates with heat exchanging means 28 through a passage 29 so that the hot gases produced in the combustor 18 are drawn into the heat exchanging means. The heat exchanging means 28 includes a chamber (not numbered) which is so located as to be in contact with the water jacket 27 of the engine cooling arrangement. A major portion of the heat in the hot gases supplied into this chamber is transferred to the water jacket 27 which is consequently warmed up to warm up, in turn, the cooling water passing through the cooling circuit 26. The heat exchanging means 28 is vented to the open air through an exhaust passage 29a leading from the passage 29. This exhaust passage 29a is preferably opened adjacent the engine air cleaner 27, carburetor 12 or intake manifold 11 of the engine 10, for the reason previously set forth.

The valve means 21 and the igniter 18a of the combustor 18 are actuated under the control of an electric control circuit which is completed when the temperature of the engine cooling water is lower than a predetermined level. This electric control circuit is entirely similar to the control circuit of FIG. 3 and includes a power source 22, thermally actuated switch means 23 and an ignition switch, and is connected to the igniter 18a and control means 21a for the valve means 21.

The arrangement shown in FIG. 4 is advantageous not only for warming up the engine cooling water at an earlier stage but for warming the combustible mixture flowing through the intake manifold 11 so as to promote the atomization of the mixture to accordingly improve the combustion efficiency of the engine, eventually contributing to reduction of the concentrations of the unburned hydrocarbons and carbon monoxide in the exhaust gases.

The embodiments shown in FIGS. 3 and 4 are useful where it is desired to use a liquefied fuel gas as the source of working fuel. If preferred, however, the working fuel may be the fuel for the engine. An apparatus adapted for this scheme is shown in FIG. 5.

The apparatus shown in FIG. 5 is essentially similar to the apparatus of FIG. 3 except for the fuel supply arrangement and, as such, description on the parts having their counterparts in FIG. 3 as designated by common reference numerals is herein omitted for brevity purposes.

Referring now to FIG. 5, the fuel for the engine 10 is supplied through a fuel passsge 30 which leads from a float chamber (not shown) and opens into the carburetor 12, as customary. The fuel passage 30 is provided with a pump 31 for pumping off the liquid fuel to the carburetor 12. I

A branch passage 32 leads from the fuel passage 30 downstream of the pump 31 and communicates with an evaporator 33 through a normally closed valve means 34 which is associated with control means 34a. The evaporator 35 includes an electrically actuated heater 33a and a spring-loaded one-way check valve 33b for preventing the fuel from flowing in the reverse direction. The evaporator 33 is thus adapted to atomize the fuel supplied thereto and the thus atomized fuel is supplied to the fuel injection nozzle 16 through the passage 17.

The valve means 34 and the heater 33b of the evaporator 33 as well as the igniter 18a of the combustor 18 are operated by an electric control circuit which is essentially similar to the control circuits of FIGS. 3 and 4. In this instance, the igniter 18a, the control means 34a of the valve means 34 and the heater 33a are connected in parallel to the electric control circuit and are energized concurrently. The valve means 34 may be. a solenoid actuated valve, in which instance the control means 34a may be a solenoid coil.

When, in operation, the temperature of the engine cooling water is lower than a predetermined level, then the switch means 23 of the electric control circuit closes with the result that the valve means 34 is opened and the heater 33a of the evaporator 33 and the igniter 18a of the combustor 18 are caused to fire. The fuel in the fuel passage 30 is thus passed to the evaporator 33 through the branch passage 32and the valve means 34 and is heated and gasified into atomized fuel through firing of the heater 33a. The atomized fuel is supplied to the combustor 18 through the injection nozzle 16 for being combusted therein. The resultant hot gases are passed to the heat exchanging means 19 to warm up the cooling water flowing through the cooling circuit 14.

When the cooling water is warmed up to the predetermined temperature, then the switch means 23 opens so that the valve means 34 is closed and the heater 33a and the igniter 18a cease firing.

In the arrangement shown in FIG. 5, the fuel pump 31 may be an electrically operated pump which can be driven with the engine kept inoperative, whereby the valve means 34 can be actuated even before the engine is started.

The embodiments which have heretofore been described are adapted to achieve the purpose of reducing the concentrations of the unburned hydrocarbons and carbon-monoxides by warming up the engine cooling water in a relatively short while. Such purpose is invariably achieved by positively warming up the lubricating fluid for the engine during engine warm-up operation, as previously discussed. An embodiment realizing this concept is now illustrated in FIG. 6.

In FIG. 6, the engine 10 is shown as comprising an intake manifold 11, a carburetor 12, an exhaust manifold 13, an air cleaner and an oil pan 35 through which the lubricating fluid or oil is circulated and recirculated during engine operations. This lubricating oil is warmed up during engine warm-up operation by an apparatus including a heat exchanging means 36 by which heat is transferred to the lubricating oil when the temperature of the lubricating oil is lower than a predetermined level.

The fuel for generating such heat is supplied from a valved source of container 37 of a liquefied fuel gas. This container 37 communicates with an injection nozzle 38 through a passage 39 in which a normally closed valve means 40 is interposed. The injection nozzle 38 extends into a combustor 41 having an igniter 41a and an air inlet port 41b. The combustor 41 is led to the heat exchanging means 36 which includes a passage passing through the oil pan 35 as illustrated. The passage of the heat exchanging means 36 is opened to the atmosphere through an exhaust passage 42. The exhaust passage 42 may be preferably located adjacent the air cleaner 25, carburetor 12 or intake manifold 11 so as to have the combustible mixture warmed up before it is supplied to the engine 10.

The valve means 40 and the igniter 41a are actuated by an electric control circuit which is responsive to the variation in the temperature of the lubricating oil. The electric control circuit comprises a power source 43 and a switch means 44 which is mounted on the oil pan 35 to the responsive to the temperature of the lubricating oil therein. The switch means 43 is normally open and is closed only when the temperature of the lubricating oil is lower than a predetermined level. The electric control circuit also comprises control means 40a for actuating the valve means 40 and is connected to the igniter 41a of the combustor 41. Designated by reference numeral 45 is an ignition switch which may be interposed in the electric control circuit where desired. The valve means 40 may be a solenoid actuated valve and, in this instance, the control means 40a associated therewith is a solenoid coil.

With this arrangement, the switch means 44 closes when the temperature of the lubricating oil in the oil pan 35 is lower than the predetermined level which may be 80C for instance. The control means 40a for the valve means 40 and the igniter 41a are thus energized. The valve means 40 is opened to cause the fuel gas to discharge into the combustor 41 through the in- 10 jection nozzle 38. The fuel gas is then combusted by the firing of the igniter 41a so that hot gases are supplied from the combustor 41 to the heat exchanging means 40. A major portion of the heat in the hot gases introduced into the heat exchanging means 36 is transferred to the lubricating oil in the oil pan 35 with the result that the lubricating oil is warmed up in a short while. The hot gases introduced into the heat exchanging means 36 are discharged out of the exhaust passage 42 and may be utilized to aid in warming up the air or the combustible mixture.

When the temperature of the lubricating oil reaches the predetermined level, then the switch means 44 opens so that the valve means 40 closes and the igniter 41a of the combustor 41 ceases firing, preventing the engine from being over heated.

FIG. 7 illustrates a modification of the apparatus of FIG. 6, wherein the fuel for warming the lubricating oil is supplied from a float chamber 46 storing the fuel for the engine 10.

The apparatus shown in FIG. 7 is constructed in a manner to warm up the lubricating oil which is circulared through a lubricating circuit 47 which includes an oil filter 47a located anterior to the oil pan 35. The heat exchanging means used in this embodiment is constituted by a chamber 48 surrounding the oil filter 47a. Hot gases are drawn into this chamber 48 from a combustor 41 in a manner described in connection with the apparatus of FIG. 6. Different from the apparatus of FIG. 6, the fuel passage 39 leading to the injection nozzle 38 is led from a space over the surface of the fuel in the float chamber 46 through a passage 49 which is vented from the atmosphere preferably through an orifice 49a and which communicates with the float chamber 46 preferably through an orifice 49b as shown. A normally closed valve means 40 is mounted intermediate the

passages

49 and 39 and is actuated by control means 40a of an electric control circuit.

The chamber 48 constituting the heat exchanging means in the shown apparatus communicates with an exhaust passage 50. The exhaust passage is led through a passage 50 into the intake manifold 11 downstream of a throttle valve 12a. a of the carburetor 12. this instance, a normally closed, electrically operated valve 51 is interposed in the exhaust passage 50, as shown. The valve 51 is actuated by control means 51a which is connected to the electric control circuit.

The electric control circuit of the apparatus of FIG. 7 thus includes the control means 51a in addition to the power source 43, switch means 44 which is closed when the temperature of the lubricating oil is lower than the predetermined level, control means 40a for actuating the valve means 40 when energized, and ignition switch 45.

When the temperature of the lubricating oil circulated through the oil pan 35 is lower than the predetermined level, the switch means 44 mounted thereon is closed to actuate the igniter 41a and valve means 40 and 51. The valve means 40 is accordingly opened so that a combustible mixture of the evaporative fuel existing over the surface of the liquid fuel in the float chamber 46 and the air supplied through the orifice 49a is passed over to the injection nozzle 38 through the

passages

49 and 39 by the aid of a suction draw from the intake manifold 11 through the exhaust passage 50, chamber 48 and combustor 41. The combustible mixture of the evaporative fuel and air is injected into the combustor 41 and is therein combusted by the firing of the igniter 41a so as to produce hot gases. The hot gases are passed to the chamber 48 by the suction from the intake manifold 11 to warm up the lubricating oil flowing through the oil filter 47a of the lubricating circuit 47. The hot gases which are introduced into the exhaust passage 50 from the chamber 48 are drawn into the intake manifold 11 through the valve 51 in the open condition to warm up the combustible mixture which is supplied to the engine 10 therethrough. When the lubricating oil in the oil pan 35 is warmed up to the predetermined temperature, then the switch means 44 opens to render the igniter 41a and the valve means 40 and 51 inoperative. The hot gases thus far supplied to the chamber 48 of the heat exchanging means is thus cut off to prevent the engine from being overheated.

If desired, the combustor 41 may be formed with an air inlet port 41c which is located adjacent an outlet of the combustor. With this arrangement, the hot gases produced in the combustor 41 are diluted with the air sucked in through the air inlet port 41c and are thereby cooled to a reasonable temperature. This is advisable because the combustible mixture in the carburetor 12 is prevented from being heated to its firing temperature by the hot exhaust gases discharged from the exhaust passage 50.

Introduction of the hot gases into the carburetor may lean out the combustible mixture to be supplied to the engine, inviting an unstable engine performance during the engine warm-up operation. To avoid this difficulty, the carburetor 12 may be arranged in a manner to produce a relatively richer combustible mixture.

FIG. 8 shows another modification of the apparatus adapted to warm up the lubricating oil during engine warm-up operation. The apparatus herein shown uses the same heating and control systems as are used in the apparatus of FIG. 5. The discussion made on the heating and control systems in connection with FIG. entirely applies to the counterparts of FIG. 8 and, therefore, common reference numerals to 13, 16 to 20, 22, 23, 25, 26 and 32 to 38 are assigned to corresponding parts. The apparatus shown in FIG. 8 is however, constructed to be adapted to warm up the engine lubricating oil and is thus associated with an engine lubricating circuit which is now designated by reference numeral 52.

The lubricating circuit 52 is led to an oil pump 52a which is indicated by broken lines and an inlet port 52b led into the engine. The lubricating circuit 52 is passed through the heat exchanging means 19 of the heating system so as to be warmed up by the hot gases produced in the combustor 18 when the temperature of the lubricating oil in the oil pan (not shown) is lower than a predetermined level. The temperature of the lubricating oil is responded to by switch means 44 which is mounted on the oil pan and which is closed when the temperature of the lubricating oil is lower than the predetermined level, similarly to its counterparts in FIGS. 6 and '7.

The combustor 18 of the apparatus shown in FIG. 8 is shown to be provided with an annular partition 18d formed around the injection nozzle 16 to define a primary air inlet port 18b for sucking in air for the combustion of the combustible mixture and a secondary air inlet port 180 for sucking in air for diluting and cooling the hot gases produced in the combustor. The

inlet ports

18b and 18c are herein shown to be located concentrically on the upstream side of the combustor 18 but the secondary air inlet port 18c may be located on the downstream side as is the case with the air inlet port 41c provided in the combustor 41 of the apparatus shown in FIG. 7.

The embodiment shown in FIG. 8 is adapted for warming up the engine lubricating oil with use of the fuel to be supplied to the engine.

FIG. 9 now illustrates an embodiment whereby both the cooling water and the lubricating oil the engine are warmed up during engine warm-up operation. The engine 10 is thus illustrated to be equipped with a cooling circuit 26 and an oil pan in addition to an intake mmanifold 11, a carburetor l2 and an air cleaner 25. The cooling circuit 26 is shown to be similar to the cooling circuit used in the apparatus of FIG. *4, branched from the engine 10 through an inlet port 26a and led to a water pump (not shown) through an inlet port 26b. The cooling circuit 26 is partly clad in a water The engine cooling water passed through the water jacket 27 and the lubricating oil in the oil pan 35, are warmed up by hot gases which are produced from a liquefied fuel gas with use of heating and control systems which are practically similar to their counterparts in the apparatus shown in FIG. 4.

In the apparatus shown in FIG. 9, however, the hot gas passage 29 leading from the combustor 18 is arranged to merge into heat exchanging means 28a and 28b which are separate from each other. The heat exchanging means 28a is actually a passage which is passed through the oil pan 35 of the engine 10 so as to warm up the engine lubricating oil drawn thereinto. The heat exchanging means 28b, on the other hand, is made up of a chamber which is in contact with the water jacket 27 thereby to warm up the engine cooling water circulated through the cooling circuit 26.

With this arrangement, when the temperature of the engine cooling water is lower than a predetermined level during engine warm-up operation, then the switch means 23 closes to complete the electric control circuit, causing the valve means 21 and igniter 18a to be actuated concurrently. The normally closed valve means 21 for the container 15 of liquefied fuel gas is opened to deliver the fuel gas to the injection nozzle 16 through the passage 17. The fuel gas is discharged into the combustor l8 and is combusted by the igniter 18a. The resultant hot gases are passed through the passage 29 first to the heat exchanging means 280. A portion of the heat in the hot gases is thus transferred to the lubricating oil in the oil pan 35 so that the lubricating oil is warmed up. The hot gases are further passed to the heat exchanging means 28b through the passage 29' whereby the heat in the hot gases is transferred to the water jacket 27 to warm up the engine cooling water in the cooling circuit 26. The hot gases from the heat exchanging means or chamber 28b are discharged through the exhaust passage 29 which may preferably be opened adjacent the intake manifold 11, carburetor 12 or engine air cleaner for the reason previously discussed. When the hot gases are passed through the second heat exchanging means 28b, the heat transferred to the water jacket 27 is imparted not only to the cooling water but to the combustible mixture flowing through the intake manifold in which the water jacket 27 is located. The combustible mixture is thus warmed up and atomized in a satisfactory condition so as to contribute to improvement of the engine combustion efficiency.

The combustor 18 may be provided with an air inlet port which is formed around the injection nozzle 16 as is the case with the inlet port 18b of the combustor in the apparatus of FIG. 4. If desired, however, the combustor 18 may be provided with a flame holder serving to balance the flame in the combustor whereby the combustion performance can be stabilized over a relatively broad range of the air-fuel ratio. In this instance, the flame holder is made up of an annular passage 53 which is formed around the injection nozzle 16 and which is led to a blower 54 through an air passage 55. The blower 54 is driven by a motor 56 which, in turn, is connected to the electric control circuit in paralle with the igniter 18a and is powered from the power source 22. Where an air injection pump is mounted on the engine for air pollution preventive purposes, the air injection pump may be utilized as the blower 54. Or otherwise, the blower 54 may be a fan for an air conditioner mounted in the motor vehicle. Provision of the flame holder thus constructed will prove useful for regulating the temperature of the hot gases produced in the combustor 18 through combustion of the liquefied fuel gas.

If further desired, the combustor for use in the apparatus of FIG. 9 may be constructed as illustrated in FIG. 10. The combustor, designated by reference numeral 18, includes inner and

outer chambers

57 and 58, respectively, both leading from the passage 62. The injection nozzle 16 and the igniter 18a extend into the inner chamber 57 and a primary air inlet port 57a is formed around the nozzle 16. The outer chamber 58 communicates with the inner chamber 57 through a secondary air inlet port 58a which is located on the downstream side of the combustor 18 as illustrated. The secondary air inlet port 58a may be so calibrated as to cool the hot gases to a controlled temperature.

The apparatus shown in FIG. 9 may be modified in numerous manners insofar as the intent of warming up both the cooling water and the lubricating oil during engine warm-up operation can be maintained. For instance, the fuel supply may be provided using the fuel for the engine as in the apparatus shown in FIG. 5, 7 or 8. Likewise the heat exchanging means 28a and/or 28b may be constructed similarly to any of those used in the apparatus shown in FIG. 3, 5, 7 and 8.

It will now be appreciated from the foregoing description that the apparatus according to this invention is adapted to reduce the concentration of the unconsumed hydrocarbons and carbon monoxide in the exhaust gases by warming up at least either of the engine cooling water and the engine lubricating oil during engine warm-up operation. The apparatus herein disclosed is thus expected to contribute to solution of the vehicular air pollution problems resulting from the use of the gasoline-powered internal combustion engines.

It should be borne in mind that the apparatus described and shown herein can be modified and changed in various manners within the scope of the claims so far as either or both of the engine cooling and lubricating media are positively warmed up during engine warm-up operation for the purpose of reducing the unconsumed hydrocarbons and carbon monoxide.

What is claimed is:

1. An apparatus for positively warming at least one of cooling and lubricating media for an automotive gasoline-powered internal combustion engine having cooling and lubricating circuits, comprising: a source of fuel; an injection nozzle communicating with said source of fuel; valve means interposed between said source of fuel and said injection nozzle actuatable to open and closed positions for controlling fuel flow from said source to said injection nozzle; a combustor into which said injection nozzle opens for delivery of fuel thereto and combustion of fuel therein and conversion of fuel to hot gas, said combustor being in association with at least one of said cooling and lubricating circuits through a passage for transferring heat from the hot gas to at least one of said cooling and lubricating media; and an electric control circuit including switch means responsive to the temperature of one of said cooling and lubricating media movable to a closed position when the temperature is lower than a predetermined level to complete said electric control circuit, control means connected to said switch means to actuate said valve means, and another control means connected to said switch means to fire fuel delivered to said combus tor.

2. An aparatus according to claim 1, wherein said source of fuel comprises a container storing a liquefied fuel gas.

3. An apparatus according to claim 1, wherein said source of fuel comprises means cooperative with a fuel supply system of said engine for supplying a combustible mixture to said injection nozzle when said valve means is open.

4. An apparatus according to claim 3, wherein said last-mentioned means comprises a branch passage branched from a fuel passage of said fuel supply system of the engine for drawing an engine fuel into said branch, said valve means being interposed in said branch passage, and an evaporator communicating with said branch passage and having a heating means connected to said electric control circuit, said heating means being actuated to atomize said engine fuel into said combustible mixture when said electric control circuit is completed.

5. An apparatus according to claim 4, wherein said evaporator further has a one-way check valve for preventing said combustible mixture from flowing back into said branch passage.

6. An apparatus according to claim 3, wherein said last-mentioned means comprises a mixture passage opened into a space over the surface of a liquid fuel in a float chamber of said fuel supply system and into the open air and communicating with said nozzle, said valve means being interposed in said mixture passage, and an exhaust passage leading from said passage of said combustor and communicating with an intake manifold of said engine for drawing a suction into said mixture passage to pass the combustible mixture into said nozzle and for warming up the engine combustible mixture with the gases discharged from said exhaust passage.

7. An apparatus according to claim 6, wherein said last-mentioned means further comprises a valve interposed in said exhaust passage and controlled by said electric control circuit to be actuated to open when the switch means is closed to complete the electric control circuit.

8. An apparatus according to claim 1, wherein said passage includes a chamber through which at least one of said cooling and lubricating circuits is passed.

9. An apparatus according to claim 1, wherein said passage includes a chamber with which at least either of said cooling and lubricating circuits is held in contact.

10. An apparatus according to claim 9, wherein said cooling circuit is partly clad in a water jacket which is located in an intake manifold of said engine and which is held substantially in contact with said chamber.

11. An apparatus according to claim 1, wherein said control means includes an igniter directed into said combustor and connected to said electric control circuit for being caused to fire when the switch means is closed to complete said electric control circuit.

12. An apparatus according to claim 11, wherein said combustor further includes means defining an air inlet port extending around said injection nozzle for supplying air into said combustor.

13. An apparatus according to claim 11, wherein said combustor further includes means defining primary and secondary air inlet ports which are separate from each other for supplying primary and secondary air into said combustor.

14. An apparatus according to claim 13, wherein said air inlet ports are vented directly from the open air.

15. An apparatus according to claim 13, wherein said air inlet ports communicate with a blower driven by a motor which is connected to said electric control circuit and which is actuated when said electric control circuit is completed for forcedly supplying air into said combustor through said primary and secondary air inlet ports.

16. An apparatus according to claim 13, wherein said primary and secondary air inlet ports are formed concentrically around said injection nozzle.

17. An apparatus according to claim 13, wherein said primary air inlet port extends around said injection nozzle and said secondary air inlet port is located on the downstream side of said combustor.

18. An apparatus according to claim 1, further comprising an exhaust passage leading from said combustor and opened adjacent one of an intake manifold, a carburetor and an engine air cleaner.

19. An apparatus according to claim 1, wherein said electric control means has interposed therein an ignition switch for said engine.

20. An apparatus according to claim 12, wherein said air inlet port communicates with a blower driven by a motor which is connected to said electric control circuit and which is actuated when said electric control circuit is completed for forcedly supplying air into said combustor through said air inlet port.

21. An apparatus according to claim 3, wherein said electric control means has interposed therein an ignition switch for said engine.

Claims

1. An apparatus for positively warming at least one of cooling and lubricating media for an automotive gasoline-powered internal combustion engine having cooling and lubricating circuits, comprising: a source of fuel; an injection nozzle communicating with said source of fuel; valve means interposed between said source of fuel and said injection nozzle actuatable to open and closed positions for controlling fuel flow from said source to said injection nozzle; a combustor into which said injection nozzle opens for delivery of fuel thereto and combustion of fuel therein and conversion of fuel to hot gas, said combustor being in association with at least one of said cooling and lubricating circuits through a passage for transferring heat from the hot gas to at least one of said cooling and lubricating media; and an electric control circuit including switch means responsive to the temperature of one of said cooling and lubricating media movable to a closed position when the temperature is lower than a predetermined level to complete said electric control circuit, control means connected to said switch means to actuate said valve means, and another control means connected to said switch means to fire fuel delivered to said combustor.