JPH0539883A - Solenoid type fluid control valve - Google Patents

Abstract

PURPOSE:To heat a solenoid type fluid control valve in a simple structure. CONSTITUTION:Besides driving current from an injection quantity control circuit 9a, high frequency alternating current from a high frequency circuit 9b is applied to electromagnetic coils 5 of a solenoid type fuel injection valve to inject fuel into an internal combustion engine. A fuel passage pipe 12 produces magnetic hysteresis loss and eddy current loss due to aternating magnetic flux caused by this high frequency alternating current, and generates heat. Furthermore, this heat is transmitted to the fuel in the fuel passage pipe 12. The fuel heated in this way is injected when a needle 4 is attracted after the driving current is supplied to the electromagnetic coils 5. In this way, by using the electromagnetic coils 5 commonly both for driving the needle 4 and for heating the fuel, the fuel injection valve can be heated in a simple structure, so that the fuel injected therefrom can be also heated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic fluid control valve for connecting and disconnecting a fluid passage, and more particularly to heating a fluid passing through the electromagnetic fluid control valve by induction heating for heating a magnetic member by a high frequency magnetic field. It is the one.

[0002]

2. Description of the Related Art Conventionally, there has been known a device which heats a magnetic member by a high frequency magnetic field and heats a fluid by the heat. For example, a fuel injection valve for supplying fuel to an internal combustion engine of an automobile is provided with a heating device by induction heating to heat the fuel injected from the fuel injection valve. 49-4525
The one disclosed in Japanese Patent No. 0 is known.

In these prior arts, a coil is provided at the tip of the fuel injection valve, and a high frequency current is passed through this coil,
The fuel injected from the fuel injection valve is being heated. As a result of the injected fuel being heated, vaporization of the fuel is promoted, starting in cold weather is facilitated, fuel efficiency is improved, and good effects are also obtained in terms of exhaust gas purification.

[0004]

SUMMARY OF THE INVENTION In the above prior art,
It was necessary to provide a coil for magnetic induction heating at the tip of the fuel injection valve. Therefore, there is a problem that the structure of the fuel injection valve becomes complicated and the physique becomes large. Further, this makes it difficult to attach the internal combustion engine to the intake manifold.

As described above, in the conventional electromagnetic fluid control valve, it is necessary to provide a special heating coil for heating the electromagnetic fluid control valve itself or heating the fluid passing therethrough. Therefore, in the conventional electromagnetic fluid control valve,
The structure was complicated.

In view of the above problems, it is an object of the present invention to provide an electromagnetic fluid control valve capable of heating the electromagnetic fluid control valve with a simple structure. Another object of the present invention is to provide an electromagnetic fluid control valve capable of heating a fluid passing through the electromagnetic fluid control valve with a simple configuration in view of the above problems.

[0007]

In order to achieve the above object, the present invention provides a valve for connecting / disconnecting a fluid passage, an electromagnetic coil for driving the valve, and a control for connecting / disconnecting a drive current to the electromagnetic coil. In an electromagnetic fluid control valve including a circuit,
The electromagnetic coil is provided with a high frequency power source for supplying a high frequency current, and a member provided inside the electromagnetic coil is caused to generate heat by magnetic induction.

[0008]

The operation of the above-described structure of the present invention will be described. The electromagnetic coil drives the valve in response to the drive current supplied from the control circuit, and interrupts the passage of the fluid to control the flow of the fluid.

Further, when a high frequency current is applied to this electromagnetic coil from a high frequency power source, the electromagnetic coil generates a high frequency alternating magnetic flux. At this time, the magnetic member through which the magnetic flux generated by the coil passes causes magnetic induction heat generation due to magnetic hysteresis loss and eddy current loss.

This heat heats the electromagnetic fluid control valve.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram showing a cross-sectional structure of a fuel injection valve of the first embodiment and a block configuration of a control device.

In FIG. 1, a bobbin 2 made of a non-magnetic material is inserted in a valve housing 1 made of a magnetic material. An electromagnetic coil 5 is wound around the bobbin 2. Further, the movable iron core 3 is inserted into the valve housing 1,
A needle 4 is connected to the movable iron core 3.

A spacer 7a is provided at the tip of the housing 1.
A nozzle body 7 is provided via the. Needle 4
Is pierced through the spacer 7a and supported by the inner peripheral surface of the nozzle body 7, and the tip of the needle 4 closes the injection port formed at the tip of the nozzle body 7. The needle 4 and the movable iron core 3 are connected to the nozzle body 7 by the return spring 6.
Is pressed against.

The electromagnetic coil 5 is connected to the electrode terminal 8 and is connected to the drive circuit 9 of the fuel injection valve by the lead wire 10. The drive circuit 9 includes an injection amount control circuit 9a and a high frequency circuit 9b.

The injection amount control circuit 9a calculates the timing of fuel injection according to the detected values of a rotation sensor and an intake amount sensor of an internal combustion engine (not shown), and at the calculated injection timing, only the time corresponding to the injection amount. , Supply drive current. Further, the high frequency circuit 9b supplies a high frequency alternating current to the electromagnetic coil 5 while the drive current of the fuel injection valve is cut off.

The electrode terminal 8 is held by a housing 11 made of an insulating material. The fuel passage tube 12 is made of iron, is inserted into the bossin 2, and is fixed to the housing 1.

Reference numerals 14, 16, 17, and 18 in the drawing are O-rings for sealing. Reference numeral 19 is a cap that protects the nozzle body. Next, the operation of this embodiment will be described.

The fuel injection valve is provided by being inserted into the intake manifold of the internal combustion engine. Fuel pressurized to a constant pressure by a fuel pump (not shown) and a pressure regulator is supplied through a pipe 13 and introduced into a fuel injection valve through a filter 15.

FIG. 2 shows the energization waveform to the fuel injection valve by the drive circuit 9 and the movement of the needle 4. When fuel injection is performed, a predetermined voltage is applied to the electromagnetic coil 5.
At this time, a current flows through the electromagnetic coil 5 to generate an electromagnetic force,
The movable iron core 3 and the needle 4 connected to the movable iron core 3 are sucked. Then, since the needle 4 and the nozzle body 7 which have been in close contact with each other are separated from each other to form a gap, the fuel pressurized to a constant pressure is injected into the intake passage of the internal combustion engine through the gap.

At this time, the electromagnetic response delay controlled by the inductance of the electromagnetic coil 5, the spring force,
Due to the mechanical relationship between the movable iron core and the needle, such as inertial force and sliding frictional force, a slight response delay (hereinafter referred to as ineffective time T from the start of energization of the electromagnetic coil to the start of suction of the needle)
d. ) Occurs. This time is usually Td = 0.
It is 2 to 0.8 (ms).

In the internal combustion engine for an automobile, the energization cycle of the electromagnetic coil of the fuel injection valve as described above is about 10 to 1.
It is 00 Hz. Next, when stopping the fuel injection, continuous energization to the electromagnetic coil 5 is stopped. Then, a high frequency high voltage (several KHz to several MHz) composed of a pulse having an ON time shorter than the ineffective time Td is applied to the electromagnetic coil 5. At this time, the needle 4 is not sucked, maintains a close contact with the nozzle body 7, and fuel injection is not executed. That is, the applied voltage is alternated before the start of needle suction by preventing continuous energization longer than the dead time Td. At this time, it is important to set the waveform of the applied alternating voltage, the maximum value, and the minimum value so that the average value of the alternating current applied to the electromagnetic coil becomes a value close to zero.

As described above, when an alternating voltage is applied to the electromagnetic coil 5, a high frequency high current flows through the electromagnetic coil 5, and a change in magnetic flux (high frequency) occurs in the fuel passage tube 12 arranged in the electromagnetic coil 5. An alternating magnetic field) is generated.

In this embodiment, as the material of the fuel passage tube 12, a metal material having particularly large magnetization hysteresis loss and eddy current loss is selected, and heat is generated in the alternating magnetic field. Then, the fuel passing through the fuel passage pipe 12 that has generated heat is heated by the heat transfer action when passing, and is injected outside from the injection valve when the needle 4 is next sucked.

In the magnetic heating means, in order to concentrate the magnetic flux density in the fuel passage tube 12 and increase the heating efficiency, the member of the valve housing 1 arranged on the outer periphery of the electromagnetic coil 5 is made of a highly transparent material such as ferrite. The magnetic susceptibility and the magnetization hysteresis loss may be small.

According to this embodiment configured as described above, magnetic induction heating can be performed with a simple structure using an electromagnetic coil for driving a needle valve. The spray of fuel heated by this embodiment has a fine particle size and mixes well with the intake air. Therefore, the homogeneous mixture can be supplied to the internal combustion engine to complete the fuel. As a result, it is possible to reduce harmful exhaust gas components (particularly HC), improve idle stability, improve smoldering resistance of the spark plug, expand the lean fuel region, expand exhaust gas recirculation amount, and reduce fuel consumption.

Next, a second embodiment to which the present invention is applied will be described. The second embodiment has the same structure as that of the first embodiment, but differs in the waveform of the current supplied to the electromagnetic coil 5.

FIG. 3 shows a drive circuit 9 according to the second embodiment.
Shows the waveform of the current flow from the fuel injection valve to the fuel injection valve and the movement of the needle 4. In the second embodiment, the high frequency alternating voltage is constantly applied to the electromagnetic coil 5, the average value of the applied voltage is increased only during fuel injection, and the needle 4 is attracted. According to the second embodiment, it is not necessary to switch between high-frequency energization and direct-current energization as in the first embodiment, and it is only necessary to add a direct-current energization component to the high-frequency energization output.

Next, a third embodiment to which the present invention is applied will be described. In the third embodiment, only the fuel passage pipe is different from the embodiment of FIG. FIG. 4 shows the fuel passage pipe 32 of the third embodiment.
FIG. The structure other than the fuel passage pipe 32 is the same as that of the first embodiment.

In this embodiment, the inner wall surface of the fuel passage pipe 32 is provided with irregularities. As a result, the contact area with the fuel can be increased, and the efficiency of heat transfer from the fuel passage 32 or the like that has generated heat to the fuel can be increased.

Next, a fourth embodiment to which the present invention is applied will be described with reference to FIG. In the fourth embodiment, the present invention is applied to an air control valve that connects and disconnects air. BACKGROUND ART Conventionally, there is known one in which air is mixed with fuel injected from a fuel injection valve and then injected into an intake manifold. Further, a technique is known in which compressed air is made to collide with fuel injected from a fuel injection valve and is supplied into an intake manifold or a combustion chamber. These techniques are effective techniques for improving atomization of the fuel supplied to the internal combustion engine of an automobile.

The air control valve of the fourth embodiment is provided in the passage of the auxiliary air mixed with the fuel, and interrupts the auxiliary air. FIG. 5 is a block diagram showing the cross-sectional structure of the air control valve of the fourth embodiment and the block configuration of the control device.

In FIG. 5, a bobbin 102 made of a non-magnetic material is inserted in a valve housing 101 made of a magnetic material. An electromagnetic coil 105 is wound around the bobbin 102. Further, a movable iron core 103 is inserted into the valve housing 101, and the movable iron core 103 is connected to a needle 104.

A nozzle body 107 is provided at the tip of the housing 101 via a spacer 107a. The needle 104 penetrates the spacer 107 a and is supported by the inner peripheral surface of the nozzle body 107.
Has a closed air outlet formed at the tip of the nozzle body 107. The needle 104 and the movable core 103 are connected to the nozzle body 10 by the return spring 106.
It is pressed against 7.

The electromagnetic coil 105 is connected to the electrode terminal 108, and is connected to the drive circuit 109 of the air control valve and the lead wire 1.
Connected by 10. The drive circuit 109 includes a control circuit 109a and a high frequency circuit 109b.

The control circuit 109a determines whether or not it is necessary to supply the atomization improving air for the injected fuel, and supplies a drive current to the air control valve when the air is supplied. Also, the high frequency circuit 109b
Supplies a high frequency alternating current to the electromagnetic coil 105 while the drive current of the air control valve is cut off.

The electrode terminal 108 is held by a housing 111 made of an insulating material. The air passage tube 112 is made of iron, is inserted into the bobbin 102, and is fixed to the housing 101.

Reference numerals 116, 117 and 118 in the drawing are O-rings for sealing. Reference numeral 119 is a cap that protects the nozzle body. The intake manifold 51 of the internal combustion engine is provided with a throttle valve 52,
A fuel injection valve 53 is provided downstream of the throttle valve 52 to inject fuel into the intake manifold.

The fuel in the fuel tank 54 is the fuel pump 55.
The fuel pressure regulator 56 adjusts the pressure to a predetermined pressure. Then, the adjusted fuel is supplied to the fuel injection valve 53. The fuel injection valve 53 is the control circuit 5
Controlled by 7, the fuel is injected at a predetermined timing according to the operating state of the internal combustion engine.

The air taken out from the air take-out port 58 provided upstream of the throttle valve 52 is pressurized by the air compressor 59 and adjusted to a predetermined pressure by the air pressure regulator 60. Then, the adjusted air is supplied to the air passage 112 of the air control valve. The air that has passed through the air control valve is supplied to the auxiliary air introduction port 61 formed in the intake manifold 51.

The auxiliary air introduction port 61 communicates with the fuel injection valve 53 immediately downstream of the fuel injection port and is injected into the intake manifold together with the fuel. At this time, the compressed air collides with the fuel injected from the fuel injection valve 53, and atomization and atomization of the fuel are promoted. As a result, a good mixture is supplied to the internal combustion engine, and good combustion is performed.

Moreover, the air control valve includes a high frequency circuit 10.
Since the high frequency current is supplied from 9b, the air control valve generates heat in the high frequency magnetic field. This prevents the malfunction of the air control valve due to freezing of the water mixed in the air supplied to the air control valve. Also,
Even if the water content in the air control valve is frozen while the engine is stopped, the air control valve generates heat when the engine is started, so that the freeze can be released to supply the auxiliary air.

According to the fourth embodiment configured as described above, magnetic induction heating can be performed with a simple structure using an electromagnetic coil for driving a needle valve. In addition, in the above embodiment, the embodiment in which the present invention is applied to the top feed type fuel injection valve has been described, but the present invention may be applied to the bottom feed type fuel injection valve.

Further, the high frequency voltage may be applied only during a predetermined period such as during winter start. By heating only when necessary, it is possible to prevent the generation of vapor due to an unnecessary increase in the fuel temperature, and it is possible to prevent a decrease in the energizing current due to an unnecessary increase in the temperature of the electromagnetic coil.

[0044]

As described above, according to the present invention, a high frequency current is passed through an electromagnetic coil for driving a valve body of an electromagnetic fluid control valve, so that the electromagnetic coil is used for driving the valve body and for heating a fluid. The fluid control valve can be heated with a simple configuration shared by the above. Therefore, it is not necessary to provide a special coil for magnetic induction heating.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of a first embodiment.

FIG. 2 is a graph showing the operation of the first embodiment.

FIG. 3 is a graph showing the operation of the second embodiment.

FIG. 4 is a cross-sectional view showing a main part structure of a third embodiment.

FIG. 5 is a configuration diagram showing a configuration of a fourth embodiment.

[Explanation of symbols]

 1 valve housing 2 bobbin 3 movable iron core 4 needle 5 electromagnetic coil 7 nozzle body 9 drive circuit 9a injection amount control circuit 9b high frequency circuit 10 lead wire 12 fuel passage pipe

Claims (1)

[Claims] 1. An electromagnetic fluid control valve comprising: a valve for connecting / disconnecting a fluid passage; an electromagnetic coil for driving the valve; and a control circuit for connecting / disconnecting a drive current to the electromagnetic coil. An electromagnetic fluid control valve comprising a high-frequency power supply for supplying an electric current, wherein a member provided inside the electromagnetic coil is heated by magnetic induction.