JPS5815622B2 - Ninen Kikanno Nenriyou Funshiya Sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a body forming an air inlet duct and a pump body for directing fuel from an inlet section toward an outlet section adapted to supply one or more fuel injectors. a pump device and a pump body provided between the inlet and outlet portions of the pump body and connected to the crankshaft or other rotary output member of the engine for delivering a metered amount of fuel toward the outlet for each operating cycle of the engine; A fuel for an internal combustion engine having a metering device driven in time relation and further comprising a sensing device adapted to sense pressure and temperature with respect to the metering device in order to obtain a suitable mixture ratio. Relates to injectors (hereinafter referred to as designated types of fuel injectors).

The present invention relates to a specified type of fuel injection device intended for use in an engine having one or more cylinders and an ignition device for igniting the air-fuel mixture in the cylinders by a spark discharge. This was done by

The invention also comprises a metering cylinder containing a free piston element or shuttle piston element movable between stops, the distance between said stops being the amount of fuel delivered during each stroke of the free piston. The cylinder spaces on both sides of the piston are connected to the pump on the one hand and the outlet on the other hand through commutation valves during continuous operation, and then this connection is reversed. It has been developed in connection with a specified type of fuel injection device, which is connected to the outlet on the one hand and the pump on the other hand, in an alternating manner.

If the fuel injection system is to be used in a multi-cylinder engine, the outlet section is provided with a plurality of outlets, and the commutator valve is combined with a distribution valve system or made as a distribution valve system, each of which is connected in an appropriate sequence. Supply fuel from the outlet.

In the operation of a given type of fuel injector, the delivery of fuel to the engine's intake manifold is continuous in groups of quantities of fuel.

The amount of each fuel group is varied by the operation of the metering device ζ, and the injected fuel groups still need to be supplied individually for proper operation at maximum speed of the engine.

Furthermore, it is important that the air intake valve of the cylinder receiving the fuel group is opened for a relatively short period of time and injects the fuel into the moving air stream so as to atomize the mixture.

This means that at the fuel outlet, for example, approximately 7 kg/i (1
In order to obtain a relatively high fuel pressure of over 00 psi),
It is necessary to provide a pump.

Now, to describe the conventional fuel injection device, U.S. Patent No. 3,
No. 625,191 "Fuel Injection Device" can be mentioned.

This device is suitable for multi-cylinder internal combustion engines and has a fuel pump, a free piston, a fuel metering device with a built-in exchange valve and a distribution valve, and the metering device is adjusted to correspond to the operating situation of the engine. It is equipped with a control device to

This control device has a bellow that expands and contracts in response to air pressure in the engine intake manifold, and a bellow that expands and contracts in response to back pressure in the engine exhaust manifold. The appropriate amount of fuel is delivered by changing the stroke of the free piston.

However, in such a fuel supply system, since the outlet pressure of the injection pump is set relatively high, there is a problem in that the necessary outlet pressure cannot be obtained when starting the engine.

In other words, 100-200 rpm when starting the engine.
Because the pump rotates at such low speed, a pump with a relatively simple structure that can be manufactured at low cost cannot generate the injection pressure necessary for the engine through the fuel injector.

To solve this problem, it has been proposed to provide a carburetor within the fuel injection device, but this method also has some drawbacks.

One of them is that the carburetor cannot be made completely inoperable during continuous operation of the engine, for example during cold weather.

Therefore, the mixing ratio cannot be determined accurately, leading to a level of air pollution that cannot be tolerated by current and future standards.

Second, it is necessary to have a complicated electrical circuit to operate the vaporizer and to stop it from operating.
As a result, the structure of the fuel injection device becomes complicated, which not only increases manufacturing costs but also causes maintenance problems and reduced reliability.

In contrast, the present invention aims to eliminate these drawbacks, and operates the carburetor installed in the fuel injection device at the time of startup, and performs fuel injection during other operating conditions. It is configured to prevent fuel from being supplied twice from both on-board injectors.

According to the invention, the air inlet duct has a cross-sectional area smaller than the cross-sectional area of the air inlet duct at a downstream position of the regulating throttle valve provided in the air inlet duct or associated with the air inlet duct; a carburetor air inlet passageway in communication with the duct and an inlet end in communication with said fuel inlet device and arranged in conjunction with the carburetor air inlet passageway to reduce the pressure within the air inlet duct to below atmospheric pressure; a fuel jet element having a fuel supply end for supplying fuel into an air inlet passageway in response to an air inlet passageway; and an air shutoff valve and a fuel shutoff valve movable from an open position to a closed position for use of fluid generated by the fuel pumping device. A specified type of fuel injection device is obtained in which a carburetor device is provided.

The term "carburizer device" refers to the air flow that moves through a fuel jet so that the fuel is broken into fine particles in the air stream and those fuel particles are carried by the air stream and vaporized before reaching the cylinders of the engine. means a device for feeding into a stream.

In one example of a simple and advantageous embodiment of the invention, the main body of the device comprises the jet element and the air cut-off valve and the fuel cut-off valve, which are closed by action of a piston element under the pressure of fuel from the pump device. The bore of the vaporizer is formed by the bore of the vaporizer such that it forms an air inlet passageway that communicates with the bore of the vaporizer at a location adjacent to the feed end of the jet element.

An air cutoff valve and a fuel cutoff valve are movable longitudinally within the bore of the carburetor and may include plungers actuated by the piston element.

The pump device can have and preferably includes two pumps.

One of these pumps is a high pressure pump mounted on the body of the device, the other is a low pressure pump,
This low pressure pump is for supplying fuel to the inlet device, and its output pressure is lower than the output pressure of the high pressure pump.

Fuel supply to the carburetor device is carried out by a low-pressure pump.

The low pressure pump can be located remotely from the body of the fuel injector, for example in the fuel tank.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

A complete fuel supply system for a fuel injection device and an example of its construction are described in British patent application no.
It is explained in detail in No. 72.

Before explaining in more detail the fuel supply device and the fuel injection device of the embodiment of the fuel injection device of the present invention, an example of the fuel supply device and its structure described in the above-mentioned patent application will be explained.

The fuel supply system shown in FIG. 1 includes a fuel tank 10. The fuel supply system shown in FIG.

From this fuel tank, fuel is supplied from a pipe 11 to an inlet of a fuel injection device 15 through a filter 12, a low pressure pump 13, and a pipe 14.

Excess fuel is returned to tank 10 via pipe 32.

The fuel injection system 15 is shown in FIG.

This internal combustion engine 17 has fuel injectors 26, which are supplied with fuel by a pipe 27 from the outlet of the fuel injection device.

Fuel injector 26 includes a spring loaded injection valve.

These injection valves are normally closed, but open in response to a predetermined injection pressure of fuel supplied to the injector.

A rotary vane high-pressure pump 18 generates the required injection pressure and supplies fuel, such as petroleum, from its inlet side 14a via a diversion and distribution valve arrangement 19 to a metering device 20.

The valve 19 functions as a free piston 20a of the metering device 20 and also serves to continuously distribute fuel to six outlet sides connected by pipes 27 to the injector 26.

Excess fuel is returned to pipe 32 via blow-off valve 31.

This measuring device is as follows.

That is, when high-pressure fuel is supplied to the cylinder space S1, the other cylinder space S2 is already filled with fuel.

Then, by supplying high pressure fuel to Sl, the free piston 2
When 0a is pushed in, the fuel filled with Sl is
From the outlet port it is sent via pipe 27 to the respective injector 26.

Next, the situation is reversed, high-pressure fuel is supplied to S1, the free piston 20a is pushed in the opposite direction, and the fuel already filled in S1 is transferred from the outlet port to the pipe. 27 to the respective injectors 26.

In this way, when high pressure fuel is supplied to one of Sl, Sl, the other is already filled with fuel, and this is done alternately at 81 and 82.

By reciprocating the free piston 20a, an appropriate amount of fuel is supplied to the cylinder according to its stroke.

The stroke of the piston 20'a of the metering device 20 between the stops 20b and 20c is determined by the detection device 29.

The metering device includes an evacuated bellows 29a to detect the absolute pressure within the chamber 34.

The chamber 34 forms part of an air inlet duct in which the intake of air is controlled by a throttle valve section 35 having a manually operable butterfly valve plate 36.

The air temperature in the chamber 34 is detected by a wax capsule temperature sensing element 37 and other temperature parameters, such as the temperature of the engine coolant, are detected by a temperature sensing device 38.

The mechanical outputs in the form of axial displacements of the temperature sensing elements 37 , 38 are summed inside the summing mechanism 39 .

The output element of this mechanism is a rotating sleeve 40, onto which one end plate of the bellows 29a is fixed.

Attached to the other end plate of the bellows is a cam element 41 which detects the axial displacement of the cam as a result of the pressure detected by the bellows 29a and the temperature sensing element 37.3.
A frustoconical cam eccentric to the axis 41a so that the rotation of the cam resulting from the temperature detected by 8 is amplified and applied to the tappet 42 which adjusts the position of the lower stop of the metering piston. It has a surface.

FIG. 5 shows the overall structure of the metering device 20 and the commutation and distribution valve device 19, and the mode of operation thereof.

Rotating valve plates 48, 49, which are fixed to each other, are supported and rotated by the carrier 47, forming a T-shaped cavity in the left side of the valve plate 48.

The rim b6 of this T-shaped cavity is made longer than the other rims b2 and b4 so as to overlap the port d of the plate 49.

The rotary valve plate 1-48.49 has ports designated by the letters t), C+f, and the subscripts 1-6 attached to these letters indicate specific outlets g1-g6, thus cylinders number 1 to 6 of the engine. Show the number.

Solid arrow 43 indicates high pressure pump 18 in one operating cycle.
The dashed arrow 45 shows the flow of fuel from the lower cylinder space s2 to one of the outlets g6.

In this operating cycle, the fuel from the high pressure pump is at port a.
1. The cylinder space s1 is reached through blyc1+d1.

Fuel from cylinder space s2 is transferred to ports C2, C4
and T-shaped cavity rim b4 (!1-b6 and port d +
Pass through fa + go.

An auxiliary pressure sensing device in the form of an accelerating piston 50 is rotatably mounted above the output sleeve 40 via a well-sealed bearing 51 and is moved to the right in response to sudden opening of the throttle valve. movement, causing the absolute pressure within chamber 34 to rise rapidly.

To this end, the bellows and cam element are moved to the right, lowering the stop 20c and enriching the mixture for a short time.

The bearings 51 allow air to enter slowly from one side of the piston to the other so that the spring 52 in the summing mechanism 39 causes the piston to return to its original position.

The pressure of the fuel supplied from the high pressure pump 18 is approximately 8.5
kg/cyrt (approximately 120psi), but
It is not generated at the starting speed obtained by the operation of a normal starting motor connected to the engine.

The fuel injection device of the present invention therefore includes a carburetor device 30 that operates only during startup.

It is necessary to prevent a double supply of fuel in both the carburetor and the injector of a fuel injector, thus removing fuel from the carburetor while injecting fuel from the fuel injector outlet. To prevent supplying, a control signal is applied to the vaporizer that disables its operation.

One convenient signal that can be used for this purpose is a fluid pressure signal taken from the output side of a high pressure pump.

Figures 3 and 4 show this carburetor in detail.

The carburetor includes a carburetor hole 100 formed in the body 33 of the fuel injector.

This carburetor hole is provided between the drive shaft and the bellows along an axis parallel to the drive shaft and the bellows.

The wall of the body 33 forms the boundary between the chamber 34 and the chamber in which the metering cylinder block, the commutation and distribution valve arrangement and the high-pressure pump are housed.

The vaporizer bore 100 includes a large diameter portion 101 and a small diameter portion 102.

Within portion 102 is one element 1 of the jet assembly.
03 is slidably attached.

The element includes an inner tube 104 in which is provided an axially extending fuel passage 105 terminating in an enlarged diameter end 106 containing a control valve.

The control valve includes a valve seat 107, a ball 108, and a helical spring 109 pressing the ball against the valve seat 107.

A hole 110 is provided in the end face of the valve seat, through which the liquid fuel system can pass into the annular space 111.

The annular space 111 has an inlet 1 of the main body of the fuel injection device.
Fuel is supplied through a passage 136 connected to 4a.

The strength of the spring 109 is set to a constant pressure, such as about 0.2 kg/C11f (about 2 psi), which is higher than the gravitational pressure of the fuel at the valve, but lower than the fuel injection pressure.
is selected to open the control valve.

This pressure is generated by a low pressure fuel pump 13.

The valve thus prevents fuel from flowing through the carburetor due to gravity when the engine and fuel injectors are not operating.

Valve element 103 also includes a head 113 that is closely fitted within the reduced diameter portion 102 of the vaporizer bore.

A sealing ring 114 is attached to this valve element.

This sealing ring 114 is mounted in the groove and seals the annular space 111 from the rest of the vaporizer bore.

The jet assembly includes a jet element 115 in the form of an outer tube that fits into the inner tube 104 like a telescope tube.

In the wall of this jet element, in a position near the free end of the inner tube 104, holes 11 constituting jet outlets at both ends of one diameter.
6 is provided.

The carburetor is equipped with two valves: a fuel cutoff valve and an air cutoff valve.

These valves are equipped with plungers 117.

This plunger can be actuated by a piston 117a and can be moved axially within the large diameter portion 101 of the carburetor bore between an open position and a closed position shown in FIG.

In this closed position, the inner end of the plunger 117
Large diameter section 1 near the free or feeding end of 04
01 overlaps the mouth or opening of the air passage 101b that crosses the air passage 101b.

Pipe 10 that can be connected to an air cleaner (not shown)
1a supplies air via the diameter section 101 to the air passage 101b.

The air passage 101b connects the hole of the vaporizer and the chamber 3.
4 will be contacted.

The fuel cutoff valve further includes a resilient valve element 118 located at the bottom of the bore 119 of the plunger 117.

The hole 119 is continuous with the inner surface of the outer tube 115 of the jet assembly.

Plunger 117 is biased by a helical compression spring 120 acting between head 113 and plunger 117 to hold plunger 117 in a position where both the fuel cutoff valve and the air cutoff valve are open.

The plunger 117 is inserted into the hole 123 from the outlet of the high pressure pump 18.
, 122. ．． “Space 12” through Space 131
1, it is activated to close the two shutoff valves when pressurized fuel is delivered.

Space 131 communicates with the outlet side of the high-pressure pump via hole 131a (FIG. 4).

The hole 123 is formed in an inlet plug device 125 that is screwed into the end that is threaded into the inner surface of the carburetor hole, and the sealing ring 125a is located within the inner circumferential recess of the inlet plug device.
is inserted.

The hole 123 is a restriction bushing 1 in which a control passage 127 is formed.
26, which can limit the rate of supply of pressurized fuel admitted into the space 121 and thus determine the length of the start-up period during which the carburetor remains operational.

This start-up period ends when, under the influence of the injection pressure of the fuel in the space 121, the fuel cutoff valve and the air cutoff valve are closed.

When the throttle valve of the fuel injector is closed, the muff',
=3-i When the throttle valve is slightly open, the pressure in the air inlet duct downstream of this throttle valve is low and the vibe 10
1a and the cross-sectional area of the passage 101b is the throttle valve member 35.
and the cross-sectional area of the main air inlet duct of the chamber 34, air is drawn through the vaporizer air inlet pipe 101a.

The speed of this air is faster than the speed of the air flowing along it due to the opening of the throttle valve plate 36.

Fuel entering diameter portion 101 from the outlet end of inner tube 104 through hole 116 in outer tube 115 is thus atomized as in a conventional carburetor low-velocity jet assembly, leaving the carburetor at the air inlet of a fuel injector. It is conveyed through a passage 101b that connects to the chamber 34 of the duct.

That is, the fuel sent from the low pressure pump 13 is
4 and enter passageway 136 (FIG. 3).

Then push the control valve ball 108 from the annular space 111 through the hole 110 and through the passage 105 into the cavity 1.
The air is blown out into the diameter portion 101 from the hole 116 provided in the hole 19 .

Here, the particles are turned into particles by the air introduced from the vibrator 101a, and are supplied to the chamber 34 through the passage 101b together with this air.

The carburetor supplies fuel to the engine even in the event of a failure of the high-pressure pump that prevents the pressure at the outlet side of the high-pressure pump from reaching a value that supplies fuel from the outlet side of the high-pressure pump to the injector. be able to.

Therefore, plunger 117 remains in the position shown in FIG.

In such a state, the throttle valve 36 is held slightly open in order to obtain a proper mixing ratio.

Pressure control and relief of the fuel supplied from the outlet side of the high-pressure fuel pump is regulated by a blow-off valve 31.

This outlet valve has a conical valve head 128.

This valve head is mated to the valve seat of the body 129.

The valve head 128 is pressed against the valve seat by a helical compression spring 130.

High pressure fuel is supplied to chamber 131 through hole 131a.

From this chamber fuel is passed through a filter 133 to an inner bore 134 in the body 129 of the blow-off valve.

The bleed valve 31 opens at a pressure determined by the compression spring 130 and releases excess fuel through the bleed valve bore portion 135 towards the passage 136 .

Passage 136 communicates with annular space 111 from which excess fuel is returned to the fuel tank through outlet member 112.

Although the present invention has been described in detail above, main embodiments of the present invention will be described below.

(1) The carburetor has a carburetor hole including the jet element, the air cutoff valve, and the fuel cutoff valve, and the two cutoff valves are arranged in the hole under the pressure of fuel from the pump device. A fuel injector as claimed in claim 1, wherein the air inlet passage of the carburetor is closed by action of a piston element therein, and wherein the air inlet passage of the carburetor communicates with the bore at a location adjacent to the feed end of the jet element.

(2) A control valve is provided to control the fuel supply to the carburetor, and this control valve is normally opened when the device is not in use, and the fuel injector operates to reach the critical pressure of the fuel. The fuel injection device according to claim 1 and claim 1, which are opened when the invention is completed.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing the main parts of a fuel supply system equipped with the fuel injection device of the present invention, FIG. 2 is a sectional view showing the structure of an embodiment of the fuel injection device of the present invention, and FIG. FIG. 4 is a cross-sectional view taken along line 3-3 in FIG. 2 showing a carburetor used in the fuel injection device of the invention; FIG. FIG. 5 is a diagram showing the overall configuration and operation of a metering device including a metering piston, a cylinder unit, and a commutation and distribution valve device. 15... Fuel injection device, 18... High pressure pump, 19... Commutation/distribution valve, 20...
...Measuring device, 26...Fuel injector, 29...
...Detection device, 31...Blowout valve, 35.
...Throttle valve member, 44...Measuring cylinder.

Claims (1)

[Claims] 1. A main body 33 forming an air intake duct and an inlet 1
4a to one or more outlets g1-g6, one or more fuel injectors 26 connected to said outlets, and a crankshaft or other rotating part of the engine. A metering device that sends out a metered amount of fuel from the outlet for each operating cycle of the engine driven in synchronization with the output member, and a metering device that controls the operation of the metering device and provides an appropriate amount of fuel in response to air pressure and temperature. A sensing device 29 for obtaining the air-fuel ratio and a carburetor air inlet passage 101a communicating with the air intake duct at a location downstream of the adjustable throttle valve, and a fuel jet element 104 for delivering fuel to the carburetor air inlet passage, and the carburetor. an air and fuel shutoff valve 101b that shuts off the supply of air and fuel to the air inlet passageway and the fuel jet element, respectively;
117.104° 118, the fuel injection device for an internal combustion engine includes a carburetor device 30 provided with a
0 indicates the jet element 104 and the air cutoff valve 101.
b. 117 and a carburetor hole 100 including the fuel cutoff valves 104, 118, both valves 101b. 117, 104, 118 are closed by the actuation of the piston element 117a in the hole 100, and the piston element receives fuel injection pressure from the outlet of the high-pressure pump 18 through the passages 131a, 131, 122, 123, 127. A fuel injection device for an internal combustion engine, characterized by: