JPS59141732A - Gas mixture suction apparatus of internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an air-fuel mixture (hereinafter referred to as the "mixture") through an intake passageway and an operator-operated system for controlling the flow of the mixture into the cylinders of an engine. a gaseous fuel supply system having a gaseous fuel injection valve, the gaseous fuel supply system being operable to supply gaseous fuel to the injection valve in response to certain operating conditions of the engine; and operable to control operation of the fuel injector according to these conditions, whereby the injector emits a conditioned discharge of gaseous fuel that is directed to a location within the intake passageway. The present invention relates to a multi-cylinder internal combustion engine or a mixture intake system, which is equipped with an electric control device adapted to apply at said location the flow of air passing through the engine.

International Publication No. 81100282 discloses a device for converting an internal combustion engine originally designed to run on gasoline into a liquefied petroleum gas-only engine or a dual-system fuel supply type. This includes injection valves designed to inject liquefied petroleum gas in liquid form directly into the incoming air stream to the engine. The injection valves can be actuated alternately under the control of an electric control unit which receives signals indicative of engine intake air flow and engine speed. The same device can also be used if only high pressure (gas pump pressure) Jut is sent to the injection valve.

EPC Publication No. 0 084 219 describes a device in which gaseous fuel is supplied to a single injection valve under regulated overpressure. The injection valve is spaced apart from the carburetor. The regulated pulsating discharge of the single injector is piped as a single feed into the carburetor intake passage for imparting airflow to the engine.

This injection valve is not installed to inject directly into the intake passage of the carburetor as proposed in International Publication No. 81100282, so it should be spaced apart from the engine to avoid excessive heating. Can be installed. Furthermore, if the engine is to be converted to operate on gaseous fuel, multiple gaseous fuel injections may be used such that the injector injects directly into the air stream to the engine as proposed in WO 81100282. It is easier to connect a single gaseous fuel source to the carburetor intake passage than to install a valve.

The fuel injection valve of the device disclosed in EPC publication no. The amount of gaseous fuel injected by such a digital valve is determined by the frequency of orifice openings and the time of each opening. Although digital valves are preferred, their use poses fuel distribution difficulties because it is difficult to synchronize the operation of such digital valves with the firing order of a multi-cylinder engine.3 These difficulties are discussed in EPC Publication No. 0084219 in general terms, and also describes compensation for this type of asynchrony in 1
Certain devices referred to are also described.

The aim of the invention is to avoid the drawbacks of the prior art proposals discussed above.

According to the present invention, a gaseous fuel is provided by an air-fuel mixture intake passage, a throttle valve in the intake passage operable by the operator for controlling the flow of the mixture into the cylinders of the engine, and a throttle valve in the intake passage that is operable by the operator to control the flow of the mixture into the cylinders of the engine. a gaseous fuel supply system comprising a plurality of on-off injector valves each operable to control the flow of gaseous fuel, the amount of gaseous fuel injected by each valve being dependent on the frequency of opening of the orifice and the time of each opening; a gaseous fuel supply device operable to supply gaseous fuel to an injector and operable to control operation of said injector on and off in response to certain operating conditions of the engine and in accordance with these conditions; , so that they are operated continuously and synchronously with the operation of the engine, whereby each of said on-off injectors is regulated and releases a pulsating discharge of gaseous fuel, which flows through the intake passage. an air-fuel mixture intake system for a multi-cylinder internal combustion engine, wherein all said on-off injectors have their regulated and pulsating gaseous fuel a common discharge chamber adapted to inject the discharged material thereinto, and a conduit communicating said common discharge chamber with said mixture intake passage, thereby providing said plurality of on-off injections. Individual regulated and pulsating gaseous fuel discharges continuously injected into said common discharge chamber by valves are collected in said common discharge chamber and delivered by said conduit to said mixture intake as a single supply of gaseous fuel. There is obtained a mixture intake system for a multi-cylinder internal combustion engine, characterized in that the mixture is sent to the passage.

A dual-system fuel system in which the present invention is implemented will now be described by way of example with reference to the accompanying drawings.

FIG. 1 shows that the air purifier 13 is activated by the operation of the multi-cylinder internal combustion engine 20 to which the carburetor 11 is attached.
a regulated amount of either gasoline or gas LP() at a position in said passage 10 upstream of an operator-operable throttle valve 12 in said passage 10 for mixing in the intake passage 10 of the A dual fuel supply type is shown which can be operated to supply the passageway 10 to the intake passageway 10 of the carburetor.
It communicates with the intake manifold 15 of the engine 20. Therefore, a regulated amount of gasoline or gaseous LPG supplied into the intake passage 10 is mixed with air drawn into the intake passage 10 via the air purifier 13 in the intake passage of the carburetor. The flow of the mixture formed by
An intake manifold 1 of an engine, which is regulated by a throttle valve 12 that can be operated by the driver, and to which an intake passage 10 of a carburetor is connected.
5 is distributed to each cylinder of the cylinder group to be communicated.

Many of the devices shown in FIG.
It is substantially similar to the corresponding part of a similar device described in Publication No. 219. The present invention relates to gaseous LPG of the type shown in FIG.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to the arrangement of injectors and the operation of gaseous fuel injectors to supply a regulated amount of gaseous LPG to the intake passage 10 of a carburetor.

Accordingly, the following description will relate only to portions of the type shown in FIG. For a description of a gasoline supply system and an LPG supply system that operate to deliver gaseous LPG to a gaseous fuel injector under regulated overpressure that varies with changes in engine 20 loading, see EPC Publication No. 008421.
Publication No. 9 is a reference.

A gaseous LPG injector of the type shown in FIG.
a common outlet 18 in conduit communication with the carburetor intake passage 10 via an air purifier 13;
and. The model shown in Figure 1 is also addressed by signals representing two key parameters: engine speed and the absolute pressure in the engine's intake manifold, so that the output at any instant is equal to EPC Publication No. It includes an electrical control unit 19 which is generally similar to the type of electrical control unit described in US Pat. No. 1,084,219. The electrical control unit 19 is based on EPC Publication No. 008.
It incorporates some features that are not described in Publication No. 4219, and the differences between them will be explained.

2 to 4 show that the injection valve assembly 16 includes two electromagnetic injection valves 21 mounted side by side on a common body 23.
．． 22.

Each injection valve 21 , 22 has a chamber 24 formed in the body 23 .
and the common outlet chamber 26. A common inlet 17 communicates with chamber 24 .

Here, the structure of the injection valve 21 will be explained with reference to FIG.

The structure of the injection valve 22 is similar to that of the injection valve 21, and its parts are identified in the following description by the reference numerals used to identify the corresponding parts of the injection valve 21. By adding rAJ, the injection valve 21
It will be distinguished from the corresponding parts.

Communication between chamber 24 and common outlet chamber 26 is via a respective one of two tubular bodies 28, 28A, each inserted into a respective hole extending between chamber 24 and outlet chamber 26. A tubular body 28.28A projects into the chamber 24. An O-ring 29.29A is attached to an annular shoulder formed at the bored end of each tubular body 28.28A within chamber 24. 0 ring 2
9°29A serves as a valve seat. O-ring 29°29
a respective hole 32 formed concentrically with the hole of the respective tubular body 28.28A in the part of the wall of the chamber 24 facing A;
．． A sylanger 31° 31A is slidably fitted within 32A. The end of each plunger 31, 31A close to the respective tubular body 28.28A is formed to seat in said O-ring 29.29A, and each sylunger 31.31A seats in its respective O-ring 29, 29A and its spring loaded by respective springs 33, 33A to close communication between chambers 24,26.

Each plunger 31.31A has an O ring 29.2
9A, it is still long enough to protrude from the end of the respective hole 32, 32A remote from the tubular body 28° 28A. The plunger has its respective tubular body 28.2
It has a radial 7 flange 34.34A at the end distal from 8A. This radial 7 lange 34, 34A is the terminal 3
Annular solenoid core 35 supporting solenoid winding 36.36A connected between 7°38 and between 37A and 38A
, 35A. One terminal, for example terminal 37.37A, is connected to the respective signal output of the electrical control unit 19, and the other terminal 38.38A is grounded.

During operation of the device, the solenoid windings 36.36A of the injection valves 21.21A respond to each pulse signal received from the respective solenoid actuation circuits 39.39A (see FIG. 5) incorporated in the electrical control unit 19. A voltage is applied during the pulse. Solenoid winding-wire 36, 36A
The application of K causes the respective plunger 31.31A to leave the valve seat, so that during each pulse there is communication between the chamber 24 and the outlet chamber 26, and thus the gas LPG associated with the period of the applied pulse. amount of each tubular body 2
8.28A can flow to the common outlet 18 via the holes and chambers. The action of the respective coil springs 33, 33A reseats the sylanger &1.31A at the end of each pulse.

FIG. 5 shows that the electronic control unit receives signal indications of the main operating parameters of the engine 20 from the respective converters.

Conveniently attached to the control unit 19, one tube 4
A pressure transducer 41 communicating with the intake manifold 15 at 2 senses the pressure within the intake manifold 15 of the engine 20 and derives therefrom an output signal indicative of the absolute pressure within the intake manifold as a function of engine load.

The engine speed signal is derived from the vehicle's ignition circuit by a suitable device 43, such as a four-blade switch on a Hall effect distributor.

An airflow meter 44 responsive to the flow of air through the intake passageway 10 to the engine generates a signal indicative of said airflow. A temperature sensing device 45 responsive to engine coolant temperature provides a signal indicative of said temperature. Temperature sensor 46 generates a signal indicative of the temperature. Device 47 provides a signal indicating the voltage output of the vehicle's accumulator.

The engine speed signal extracted from the vehicle's ignition circuit by device 43 is shown at the top of FIG.
Sent directly to 4. Other converters 41 and 44 to 4
The signal from 7 is sent to the in/out controller of microprocessor 51 via multiplexer 52 and analog to digital (A/D) converter 53.

The microprocessor 51 has an erasable semi-permanent memory (EpRoM) which is a memory matrix or reference memory operable under the control of the microprocessor 51.
56.

Microprocessor 51 has two signal outputs and is arranged to alternately issue output pulse signals from both sources, as further detailed in co-pending patent application Ser. Each output of the microprocessor 51 is connected to one of two solenoid operated eight circuits 39.39A.

In operation of the microprocessor 51, under the control of the central processing unit 540, the EPROM 56 is addressed with signals indicative of two primary parameters: engine speed and absolute pressure in the engine's intake manifold to generate fuel trim pulses. A signal output is issued alternately to both solenoid actuation circuits 39 and 39A.

The output pulses issued by the microprocessor assembly 51 and alternately transmitted to the solenoid actuation circuit 39.39A are connected to the solenoid winding 36 of each injector 21.22,
36A is energized once for each other firing firing of the engine 20 so that it is synchronized with the firing firing order of the engine. The width of each fuel adjustment pulse is
Define the duration of the actuation pulse from A and the amount of fuel expelled by each injection.

FIG. 6 shows the relationship between the firing order shown at the top and the solenoid application pulses issued by the respective solenoid actuation circuits 39, 39A.

Each solenoid applied pulse is applied to the valve syringe 31.31
A is followed by a steady-state portion of about 1, during which the valve's silunger 3
1.31A is in its open position. FIG. 4 shows that the valve syringe 31 has moved off the valve seat, while the valve syringe 31A is seated.

The solenoid applied pulses cause the valves to open alternately at equivalent points in the engine cycle at alternate cylinder firings, but from Figure 6, under some engine operating conditions, such as high engine speeds, others are open. It will be appreciated that it is possible for one valve to remain open.

The electric control unit 19JC controls the two injection valves 21.2.
It will be appreciated that two valves are activated in sequence so that the pulsating discharge from those two valves is collected in a common chamber 26. As a result, the injector assembly 16 pumps gas L from its common outlet 18 at a frequency synchronized with engine speed.
Releases PG.

The resulting gaseous LPG supply can merge into a nearly continuous flow at high engine speeds even though it is a pulsating discharge at low engine speeds. The gaseous LPG discharge from the common outlet 18 is conveyed to the intake passage 10 of the carburetor and is sucked into the interior of the intake passage 10 via the air purifier 13, where it is
A single supply of gaseous fuel is applied to the air flowing through the intake passage 10 toward the engine.

The injector assembly 16 is conveniently positioned to avoid overheating of the injector and conveniently mounted to minimize operational noise.

The storage matrix 56 incorporated in the electrical control unit 19 advantageously consists of 256 cycles of pulse widths in the range of 10 m5ec. An arithmetic linear interpolation process is performed over 16 steps between the storage locations of each value. To provide adequate sensitivity to low values, engine speed address steps are used in the storage matrix in a geometric progression. Addressing the engine load may be an arithmetic step.

As shown in FIG. 7, a delay device 5 between the microprocessor 51 and each solenoid operating circuit 39.39A.
With the intervention of 8.58 A, the timing of injection can be delayed in phase after each moment of ignition.

Various devices for modifying the pulse width output signal from microprocessor 51 can be provided in electrical control unit 19 in various ways. A predetermined minimum absolute manifold pressure, e.g. 0.2, to provide an overrun fuel cut-off for fuel savings and reduce exhaust emissions.
A zero value can be placed in the matrix at the engine load address under bar. A separate pulse width generator 59 (8th
(see figure) can be used. Each value may need to be modified according to the temperature of the engine coolant. Provisions can also be made to prevent excess gas from being discharged during starting if the engine fails to start. This allows the generator 59 to provide a device that reduces the starting pulse width from an initially wide pulse width of e.g. 75 m5ec to zero over a starting period of 20 sec.
This is achieved by incorporating it into a signal source that serves as a signal generator.

The two injection valves 21,22 do not have to be mounted side by side, as shown in FIGS. 2 and 4. These can be arranged so that they inject facing each other, almost coaxially, or along converging paths.
Can be installed. Alternatively, they are arranged to move laterally to each other and inject in opposite directions into interconnected passages along parallel paths;
Can be moved.

The device described above with respect to the drawings is designed for a four-cylinder engine. ! In order to facilitate the application of this device to engines having a large number of cylinders, more than two injection valves may be provided; a larger number of injection valves may be arranged to be activated sequentially in synchronization with the engine. It would be desirable to do so.

FIG. 9 shows another type of injection valve that may be used in place of the syringe type injection valve described above with respect to FIGS. 2-4. As in the plunger type injection valve 21, communication between the chamber 24 and the outlet chamber 26 is via a hole in the tubular body 28. FIG. 9 shows that the hole is provided with a step, and the diameter of the stepped hole of the tubular body 2B of the silancia type injection valve 21 increases in the downstream direction, whereas the diameter decreases in the downstream direction.

The valve member of the injection valve shown in FIG. 9 is a disk 61 having a central flat surface of larger diameter than the diameter of the O-ring 29 which together serve to close the communication between the chambers 24,26.

A spring 62 located in a hole 63 formed in the body 23 concentrically with the hole in the tubular body 28 acts to push the disc 61 against the valve seat on the O-ring 29 and to close the gap between the chambers 24 and 26. Close the communication. Ball 64 is also positioned within hole 63. When the solenoid windings 3, 6 are applied by a pulse signal received from the electric control unit 19, the disc 61 moves away from the valve seat, as shown in FIG.

The movable parts of the valve shown in FIG. 9, namely the disk 61 and the ball 64.
, can be lighter than their counterparts in the syringer valve 21, so that disc valves can operate at higher frequencies than syringer valves.

Multiple injector assemblies of this type which are operated sequentially in synchronization with engine operation to collect and deliver their regulated pulsating discharges as a single charge which is applied to the air drawn into the engine. The application of the system is not limited to its dual gasoline/LPG supply system application. This is vI
4. A regulated supply of gaseous fuel is mixed with a stream of air drawn into the internal combustion engine through an intake passage having a throttle valve therein operable by the operator to control the flow of the mixture to the engine. The present invention can be applied to any gas fuel system for a multi-cylinder internal combustion engine.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a gasoline/LP() fuel system for a four-cylinder engine incorporating two gaseous LPG injectors, and Figure 2 is a schematic diagram of a two-plunger fuel injection valve assembly used in the system shown in Figure 1. The plan view, Figure 6, is along the line l1l-I in Figure 2.
4 is a partially sectional front view of the assembly shown in FIGS. 2 and 3 with one valve seated and the other off the valve seat; FIG. 5 is a partial sectional front view of the assembly shown in FIG. Electrical circuit diagram of the valve's electric control unit and the lenoid winding, No. 6
Figure 9 is a graph showing the operation of two injection valves of the type shown in Figure 1 synchronized with the firing order of the engine; Figures 7 and 8 are diagrams showing modifications of the circuit shown in Figure 5; The figure shows another type of gaseous LPG I! used as one of the injection valves in the system shown in FIG. Figure 7 is a partial view similar to the corresponding part of Figure 6 showing the jut injection valve; 10: Intake passage 22: Injection valve 12: Throttle valve 26: Common outlet chamber 19: Electric control device 51: Microprocessor 20: Engine
56: Memory matrix 21: Injection valve 59; Pulse width generator agent Akira Asamura FIG6 FIG9 Director General of the Japan Patent Office 1. Display of the case 1982 Patent Application No. 227809 3, Person making the amendment Relationship with the case Patent applicant 4, Agent 5, Date of amendment order Month, Day 6, 1980, Number of inventions increased by amendment Engraving (no change in content J Procedural amendment (method) % formula % 1. Indication of the case Patent Application No. 227809 of 1982 2. Title of the invention 3. Person making the amendment Relationship with the case Patent applicant address 4 , Agent (nee), J 5. Date of amendment order February 28, 1980 6. Number of inventions increased by amendment 7. Drawings subject to amendment 3 (no change in content) 8. Contents of amendment As per attached sheet

Claims (1)

[Scope of Claims] (1) An intake passage for a mixture of air and fuel (hereinafter referred to as "mixture") and an intake that can be operated by the driver to control the flow of the mixture to the cylinders of the engine. a gaseous fuel supply system comprising a throttle valve in the passageway and a plurality of on-off injection valves each operable to control the flow of gaseous fuel by opening and closing a respective orifice; The amount of gaseous fuel supplied is determined by the frequency of openings of the oriice and the time of each opening, and the gaseous fuel supply device is operable to supply gaseous fuel to the injector under overpressure and is responsive to certain operating conditions of the engine. and operable to control the operation of said on-off injectors according to these conditions, such that they are operated continuously and synchronously with engine operation, whereby each of said on-off injectors is regulated. emitting a pulsating and pulsating discharge of gaseous fuel;
In the air-fuel mixture intake system of a multi-cylinder internal combustion engine, the air-fuel mixture intake system for a multi-cylinder internal combustion engine is provided with an electric control device so that it is applied to the air flow passing through the intake passage.
a common discharge chamber into which off-injector valves are adapted to inject their regulated and pulsating discharge of gaseous fuel; and a conduit connecting said common discharge chamber to said mixture intake passage. the plurality of on-off injector valves continuously injecting into the common discharge chamber the individual regulated and pulsating gaseous fuel discharges that are continuously injected into the common discharge chamber; A mixture intake system for a multi-cylinder internal combustion engine, characterized in that a single supply gaseous fuel is sent to the mixture intake passage through the conduit. (2) The apparatus of claim 1, wherein the electrical control unit includes a microprocessor incorporating a memory module (IJ) and various engine control systems responsive to specific operating conditions of the engine, including engine speed and engine load. a microprocessor having an input arranged to receive a signal from each transducer and such that the storage matrix is addressed by the signal indicative of parameters of engine speed and engine load; A continuous output signal generated from information stored in the injector is alternately applied to a voltage applying device of each injector that can be operated electromagnetically, thereby continuously operating the injector. Device. (3) An apparatus according to claim 1 or 2, wherein the electric control unit is pressurized to cut off the fuel when an engine overrun condition is sensed. (4) The apparatus of claim 3, wherein the electrical control device installs a zero value in the storage matrix at a location addressed by a signal indicative of an engine intake manifold pressure condition below a certain minimum manifold pressure. A device adapted to perform this type of fuel cut-off. (5) In the device according to any one of claims 1 to 4, the electric control device controls the operation of each injector at predetermined time intervals from the moment of each ignition combustion. equipment arranged to do so. (6) The device according to any one of claims 1 to 5, wherein the electric control device generates a wide pulse width for actuating the injection valve for a side start operation. Apparatus adapted to include a separate pulse width generator adapted to. In the apparatus according to claim 6, the separate pulse width generating device converts the pulse width signal emitted by the separate pulse width generating device into an initial wide pulse width signal for a predetermined period of time. (8) In the device according to any one of claims 1 to 7, each injection valve is a silanger type injection valve. Device. (9) The device according to any one of claims 1 to 7, in which each injection valve is a disk type injection valve. QOI Claim 1 Apparatus according to any one of clauses 9 to 9, wherein the electrical control device is adapted to open each valve during certain engine operating conditions before the other valves close.