JP6072882B1 - Fluid control valve and internal combustion engine using the same - Google Patents

Abstract

The present invention provides a fluid control valve having a low cost and high reliability, and an internal combustion engine using the same while dramatically improving the fluid controllability of the automatic valve while utilizing the function of the automatic valve by self-excited vibration. It is an object. A fluid injection valve 1 generates a core 5 having a tapered surface 5a, an armature 7 having a tapered surface 7a, and an electromagnetic force for slidingly driving the armature 7 on opposite surfaces. The solenoid coil 6 is configured to include a valve 9 held by the armature 7, a valve seat 10 for seating the valve 9, and a spring 11 that biases the armature 7 toward the core 5. The armature 7 is slid by the applied current, and the flow rate of the fluid discharged by the self-excited vibration of the valve 9 is controlled by adjusting the gap amount between the valve 9 and the valve seat 10. [Selection] Figure 1

Description

  The present invention relates to a flow control valve used for a fluid injection valve for fuel injection for an automobile, and an internal combustion engine using the same. It is.

  There are various so-called fluid control valve drive sources such as an electromagnet (solenoid), a motor, heat (temperature), and fluid pressure. Generally, a fluid control valve that is widely used in the industry is a spring-mass. The system is roughly classified into a mechanical automatic valve by mechanical (fluid, heat) control such as a system (for example, see Non-Patent Document 1) and an electronic control valve by electronic control using a solenoid or a motor. In addition, there are various types of valve forms and control methods, and various fluid control valves have been developed and used by combining them.

  These fluid control valves are required to have more advanced functions and characteristics in various systems, but also to be cheaper and easier to use. In response to these demands, various improvements and developments such as materials, processing methods, assembly methods, and accuracy improvements have been made so far in terms of manufacturing and production technologies. In addition, on the design side, improvements and developments such as reduction in size and weight, improvement in responsiveness, expansion of dynamic range, improvement in accuracy, reduction in variation, and addition of functions have been performed. In particular, in the case of electronic control valves, their functions and characteristics have made great progress due to the advancement of control methods, the ability of control circuits, and the improvement of reliability.

  However, in electronic control valves, there is no change in using solenoids and motors as drive sources, and therefore there are limits to the efficiency design of magnetic circuits and the improvement of valve systems. Therefore, in recent years, many methods have been proposed to improve functions and characteristics by using separate solenoids for valve opening and closing operations, or using solenoids and permanent magnets in combination, for example. Has been. However, these methods are not necessarily cost-effective due to the increase in size and cost of the fluid control valve. That is, when two solenoids are used, electric energy is newly consumed, and when a permanent magnet is used, the maximum energy required for the permanent magnet must be given. Regardless of whether or not the system is in operation, useless energy is required.

  Also, new actuators that use piezo elements as drive sources have been put into practical use, but the objects and markets used are limited in terms of reliability and cost. Also, the automatic valve has been used for a long time, but has not been significantly changed as a drive source or a valve form, and has been treated as a category different from the electronic control valve.

  Therefore, for example, in the fuel injection nozzle of Patent Document 1, a fuel passage into which pressurized fuel is introduced, an electromagnetic valve that opens and closes the fuel passage, a fuel reservoir chamber that communicates with the fuel passage via the electromagnetic valve, and a fuel reservoir An automatic valve that opens and closes according to the pressure of fuel in the room, an electromagnetic coil that can urge the automatic valve in the opening and closing direction, and an energization control means that controls energization of the electromagnetic coil according to the operating state of the engine Since the valve opening pressure of the automatic valve is controlled in accordance with the operating condition of the engine, the response of the fuel injection nozzle can be improved even when the pressure of the atmosphere to be injected is low. The amount can be reliably controlled. Further, it has been proposed that even when the pressure of the atmosphere to be injected is high, the valve opening pressure of the automatic valve can be reduced, so that fuel injection becomes possible.

  Moreover, in the excitation type fuel supply device of Patent Document 2, the fuel discharge portion is configured by a valve, a valve seat, and a spring, and at least when the movable cylindrical portion that supports the valve is forcibly excited by an external signal, at least the valve is While the self-excited vibration is generated, the excitation source is forcibly vibrated by driving the power transistor by modulating the clock frequency by the microcomputer. As a result, in a self-excited vibration valve in which vibration conditions are determined by fuel pressure, spring and pipe diameter, pipe length, etc., even if low pressure fuel and low quality fuel (poor vaporization, high viscosity, etc.) are used, A fuel supply system capable of sufficiently atomizing fuel has been proposed.

"Hydraulic control", Takenaka / Urata, Maruzen Co., page 95

Japanese Utility Model Publication No. 58-86473 JP 58-158366 A

  However, in the fuel injection nozzle of Patent Document 1, a part of the magnetic circuit of the electromagnetic mechanism is connected to the end of the automatic valve so that the valve opening pressure of the automatic valve can be changed by the operation of the electromagnetic mechanism. It contributes to control. That is, by connecting separate mechanisms such as an automatic valve and an electromagnetic mechanism, the respective functions are also combined. However, the overall apparatus has been a factor in increasing the size and cost. Further, since the new electromagnetic mechanism is immersed in the fluid, there are many reliability problems. Further, the control by the electromagnetic mechanism is positioned as an auxiliary means for achieving optimization of the flow rate control, and there is no idea or intention of actively performing the flow rate control. In the normal solenoid used here, it is difficult to finely control the armature stroke, and there is a problem that the controllability of interest is insufficient.

  Further, in the excitation type fuel supply device of Patent Document 2, a moving coil actuator is connected to an automatic valve, and self-excited vibration of the automatic valve is controlled to maintain atomization. In other words, by connecting separate mechanisms such as an automatic valve and a moving coil, the respective functions are also combined. Thus, the self-excited vibration frequency is optimized by controlling using the moving coil. Since the coil is arranged directly in the fuel, there is a great reliability problem. In addition, the control by the moving coil is just an auxiliary means of optimizing the self-excited vibration frequency, and there is no idea or intention to actively control the flow rate. There was a problem of being insufficient.

  The present invention has been made in order to solve the above-described problems. While taking advantage of the function of the automatic valve by self-excited vibration, the fluid controllability of the automatic valve is drastically improved, and the reliability is reduced at a low cost. An object of the present invention is to provide a highly fluid control valve and an internal combustion engine using the same.

In order to solve the above-described problems, a fluid control valve according to the present invention is fixed to a cylindrical body and an inner wall of the cylindrical body, and has a fluid flow path, and the fluid inlet is provided on one side. A fixed iron core having an outlet having a tapered surface formed on the other side, and is held on the inner wall of the cylindrical body so as to be slidable in the axial direction, and has a fluid flow path. A movable iron core having a tapered surface formed opposite to the tapered surface of the movable iron core, and the fluid core is floatingly held by the movable iron core so that the fluid can flow on the opposite side of the tapered surface of the movable iron core. A valve, a valve seat fixed to the cylindrical body and seating the valve, a solenoid coil that generates electromagnetic force for slidingly moving the movable iron core in the axial direction, and a direction of the movable iron core toward the fixed iron core biasing the both pressure the urging force of the fluid And an elastic body is configured so as to enable self-excited vibration of the valve against the movable iron core by current supplied to the solenoid coil is slid, with said valve seat and said valve The flow rate of the fluid to be discharged is controlled by adjusting the gap amount.

  According to the fluid control valve of the present invention, the opposed surfaces of the fixed iron core and the movable iron core are tapered, and the movable iron core is configured to hold the elastic body that urges the valve. The controllability of the valve is dramatically improved, the degree of freedom of flow rate control and spray control is greatly improved, the number of parts can be reduced, and the size and weight can be reduced.

1 is a cross-sectional view showing the overall configuration of a fluid control valve according to Embodiment 1. FIG. It is sectional drawing which shows the whole structure of the other embodiment of the fluid control valve which concerns on Embodiment 1. FIG.

  Hereinafter, the configuration and operation of the fluid control valve according to the embodiment of the present invention will be described in detail with reference to FIG. Here, a fluid injection valve for fuel injection used in an internal combustion engine will be described as an example of the fluid control valve.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing the overall configuration of the fluid control valve according to the first embodiment.

  First, the configuration of the fluid control valve according to the first embodiment will be described with reference to FIG. A fluid injection valve 1 that is a fluid control valve includes a solenoid mechanism 2 that is an electric drive mechanism and a valve mechanism 3 that is a non-electrically driven valve mechanism.

  As shown in FIG. 1, the solenoid mechanism 2 fixes a core 5 that is a fixed iron core, an armature 7 that is a movable iron core provided with a magnetic gap d to the core 5, and the core 5. A cylindrical body 8 that houses the armature 7 so as to be slidable in the axial direction (Z-axis direction in FIG. 1), and a solenoid coil 6 that generates electromagnetic force that slides the armature 7 in the Z-axis direction. And a housing 4 for housing them. Here, on each surface where the core 5 and the armature 7 face each other, a core-side tapered surface 5a formed with a conical outer surface shape and an amateur-side tapered surface 7a formed with a conical inner surface shape are formed. ing.

  Here, the magnetic gap d is the shortest distance between the core-side taper surface 5a and the amateur-side taper surface 7a (distance in a direction perpendicular to both taper surfaces), but the position of the core 5 is used as a reference. The slidable distance of the armature 7 in this case is the movement distance in the Z-axis direction shown in FIG. That is, since the opposing surfaces of the core 5 and the armature 7 are tapered, it is possible to increase the movable distance of the amateur with respect to the gap as compared with the case where the opposing surfaces in a normal solenoid mechanism are flat surfaces. Thereby, the position of the amateur can be determined at an arbitrary movable distance. The solenoid mechanism 2 is a linear drive type solenoid mechanism in which the magnetic attraction force with respect to the gap is gently increased and the sliding distance range of the armature 7 with respect to the core 5 is increased.

  The valve mechanism 3 holds the valve 9 held by the armature 7, the valve seat 10 on which the valve 9 is seated, the spring 11 that is an elastic body that biases the armature 7 toward the core 5, and the spring 11. Amateur 7 to be made. Here, the armature 7 of the solenoid mechanism 2 also has a function as a spring holder of the valve mechanism 3 that holds the spring 11. The valve 9 is a so-called external valve, and is an automatic valve in which the valve opening operation direction of the valve 9 is the same as the fluid outflow direction (here, the Z-axis direction). The valve body surface of the valve 9 that is in contact with the valve seat 10 is formed in a conical shape or a spherical shape including multiple stages, and the valve seat surface of the valve seat 10 that is in contact with the valve 9 is a circle having an edge shape or an inner surface having multiple stages. It is formed in the shape of a cone including it. A groove (not shown) for allowing fluid to flow is formed on the contact surface 7c of the armature 7 that contacts the valve 9.

  Further, the spring 11 acts in a direction of pressing the valve 9 against the valve seat 10 with a predetermined load. In addition, the seat surface holding the spring 11 is the valve seat 10 and the seat surface 7 b of the amateur 7. The predetermined load applied to the spring 11 overcomes the predetermined load of the spring 11 when the pressure of the fluid flowing into the fluid injection valve 1 reaches a desired value, the valve 9 is pushed down, and the valve 9 is opened. Is set to When the pressure of the inflowing fluid increases and the valve 9 is opened, the pressure of the fluid in the fluid injection valve 1 decreases, so that the valve 9 is closed again by the restoring force of the spring 11. Actually, the continuous flow is adjusted by adjusting the volume and pressure loss in the fluid injection valve 1 and the relationship between the lift and the opening area of the valve 9 so that the fluid pressure is restored before the valve 9 is closed again. Set to maintain. Further, in order to stabilize this continuous flow, the valve 9 is caused to self-oscillate with a predetermined lift as an average. In other words, the self-excited vibration keeps the pressure of the fluid in the fluid injection valve 1 constant. The self-excited vibration condition is determined by the spring-mass (mass) system of the valve mechanism and the fluid vibration system of the inner pipe portion of the fluid injection valve through which the fluid flows. It functions as an automatic valve that injects a constant flow rate.

  Next, the operation of the fluid injection valve 1 when supplying fuel to the internal combustion engine will be described with reference to FIG. For example, when the fuel is introduced from the inlet 1a of the fluid injection valve 1, the fuel passes through the flow path of the core 5 and the armature 7, the internal pressure of the fuel overcomes the extension force of the spring 10, the valve 9 is pushed down, The valve 9 is pushed down at a contact portion 12 between the valve seat 10 and the valve seat 10 to create a gap, thereby opening the valve 9 and injecting fuel to the outside. When the fuel is injected from the contact portion 12 by opening the valve 9, the internal pressure of the fuel in the fluid injection valve 1 is reduced, the extension force of the spring 11 is lost, and the armature 7 is pushed up. Since it is held by the contact surface 7 c of the amateur 7, the valve 9 is pushed up, the valve 9 is pushed up by the contact portion 12 between the valve 9 and the valve seat 10, and the valve 9 is closed. As a result, the internal pressure of the fuel rises again and the valve 9 is opened. Similarly to the above-described contents, by setting various conditions so that the pressure of the fluid is restored before the valve 9 is closed, it is possible to obtain a continuous flow and further to make a self-excited vibration. . In this way, the opening and closing of the valve 9 is automatically repeated by self-excited vibration, and a certain amount of fuel is continuously injected. Here, the biasing force of the spring 11 is set so that the self-excited vibration of the valve 9 can be stabilized and continued with respect to the pressure by the fuel.

  Usually, the automatic valve based on self-excited vibration has a stable continuous flow and relatively good response controllability when a constant flow rate of fluid is injected in a state where the valve 9 is opened relatively stably. . However, when the flow rate of the fluid is small, after the valve 9 is opened and the fluid is injected at once, the valve 9 is closed until the fluid is refilled in the fluid injection valve 1. become. That is, the fluid becomes an irregular intermittent flow, and it becomes difficult to control the flow rate.

  Further, when the valve 9 is stably opened, the jet (spray) can be atomized by self-excited vibration. However, when the valve 9 is not stably opened, it is difficult to generate self-excited vibration, and therefore the jet (spray) cannot be atomized.

  Therefore, in the fluid injection valve 1 of the present embodiment, an electromagnetic force generated in the solenoid coil 6 by energization generates an attractive force between the core 5 and the armature 7, thereby moving the armature 7 in the axial direction, By applying a bias to the lift position of 9, the valve 9 can be stably opened and the self-excited vibration can be stabilized.

  In addition, by energizing the solenoid coil 6, the lift amount of the valve 9 can be adjusted to stabilize the self-excited vibration, and the flow rate can be adjusted. For example, by reducing the size, it is possible to stably reduce the opening area at the time of opening the valve, and the valve opening time can be increased for the same flow rate control. In addition, stabilization during minute flow rate control can be achieved. Also, by changing the lift amount, changing the opening area at the time of opening the valve changes the flow direction and slightly changes the spray angle, so that the spray angle can be controlled. Furthermore, the movement amount of the armature 7 can be finely adjusted by making the opposing surface of the core 5 and the armature 7 into a tapered shape.

  Here, the position of the armature 7, that is, the lift amount of the valve 9 is determined by the electromagnetic force by the solenoid coil 6 and the biasing force by the spring 7. Further, the lift amount of the valve 9 is adjusted by changing the energization amount of alternating current or direct current that is energized to the solenoid coil 6.

  Further, in the fluid injection valve 1 of the present embodiment, a new function is added by incorporating a control function by the solenoid mechanism 2 into the valve mechanism 3. That is, by integrating the spring holder of the valve mechanism 3 and the armature 7 of the solenoid mechanism 2 and linearly driving the armature 7, the valve opening lift operation of the valve 9 can be controlled substantially precisely. . By integrating the spring holder and the armature 7, the mechanical parts can be simplified and the number of parts can be reduced.

  As another embodiment of the fluid injection valve according to the first embodiment, as shown in the fluid injection valve 100 in FIG. 2, the taper formed on the core 5 and the armature 7 has a tapered surface 51a on the core side having a conical shape. It may be an inner surface shape, and the tapered surface 71a on the amateur side may be a conical outer surface shape.

  As described above, according to the fluid injection valve according to the first embodiment, the spring holder of the valve mechanism and the armature of the solenoid mechanism are integrated, and the opposing surfaces of the core and the armature are tapered. The movable range of the amateur can be increased, the flow rate control range can be expanded, and the stabilization during the minute flow rate control can be achieved.

  In the fluid injection valve according to the first embodiment, by adjusting the position of the armature 7 by energizing the solenoid coil 6, the lift amount of the valve 9 is adjusted to force the valve 9 being opened. It is also possible to close the valve. For example, by periodically energizing the solenoid coil 6 with a pulse current, the valve 9 is opened periodically by self-excited vibration and synchronized with the cycle of the internal combustion engine so that fuel injection is not continuous injection. Intermittent injection is also possible. Further, by controlling the pulse width of the pulse current, the valve closing period can be controlled to control the injection flow rate.

  In the fluid injection valve according to the first embodiment, the solenoid coil 6 is energized with a pulse current superimposed on a direct current, so that the valve opening by self-excited vibration can be stabilized, and the flow control in a minute flow rate region. Is possible. Thereby, the flow rate control range can be further expanded.

  Further, in the fluid injection valve according to the first embodiment, the solenoid coil 6 can be used as an automatic valve by only self-excited vibration without energizing the solenoid coil 6, that is, without operating the solenoid mechanism 2. It is also possible to eject the fluid with only 3. In this case, since no power is consumed, an energy saving operation can be performed as necessary.

  In the first embodiment, a fluid injection valve for fuel injection used in an internal combustion engine for a vehicle has been described as an example of a fluid control valve. Is also applicable.

  In the first embodiment, the case where the coiled spring 11 is used as the elastic body has been described. However, the present invention is not limited to this, and it is sufficient that there is a repulsive force. Good.

  Note that the present invention is not limited to the above-described embodiment, and the embodiment can be appropriately modified and omitted within the scope of the invention.

  Moreover, in the figure, the same code | symbol shows the same or an equivalent part.

1,100 Fluid injection valve, 2 Solenoid mechanism, 3 Valve mechanism, 4 Housing, 5 Core,
5a, 51a Tapered surface on the core side, 6 solenoid coil, 7 amateur, 7a,
71a Tapered surface on the amateur side, 7c Contact surface, 8 Tubular body, 9 Valve, 10 Valve seat, 11 Spring, 12 Contact part

Claims (4)

A tubular body;
A fixed iron core fixed to the inner wall of the cylindrical body, having a fluid flow path, having the fluid inlet on one side, and having an outlet formed with a tapered surface on the other;
A tapered surface is formed on the inner wall of the cylindrical body so as to be slidable in the axial direction and has a flow path for the fluid, and is disposed to face the tapered surface of the fixed iron core with a gap. A movable iron core,
A valve that is held floating by the movable core so that the fluid can flow on the opposite side of the tapered surface of the movable core;
A valve seat fixed to the cylindrical body and seating the valve;
A solenoid coil that generates electromagnetic force for slidingly moving the movable iron core in the axial direction;
An elastic body that urges the movable iron core in the direction of the fixed iron core and is set such that the urging force enables self-excited vibration of the valve with respect to the pressure of the fluid ;
The movable iron core is slid by an electric current supplied to the solenoid coil, and a flow amount of the fluid to be discharged is controlled by adjusting a gap amount between the valve and the valve seat. Fluid control valve. The fluid control valve according to claim 1 , wherein a pulse current is applied to the solenoid coil. The fluid control valve according to claim 1 , wherein a pulse current is applied to the solenoid coil so as to be superimposed on a direct current. An internal combustion engine, wherein the fluid control valve according to any one of claims 1 to 3 is used as a fuel injection valve for supplying fuel.

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