JPH0893576A - Vapor fuel control valve device - Google Patents

Abstract

PURPOSE: To provide a vapor fuel control valve device which can be opened under three-patterns of valve opening conditions and has a simple structure. CONSTITUTION: When an electric current is applied to an electromagnetic solenoid 2, a moving core 10 is attracted against the elastic force of a coil spring 11, and moreover a magnetic pole formed on a face opposite to the moving core 10 alters according to a current applying direction. When the moving core 10 and a permanent magnet 19 are mutually attracted, a canister passage 15 opens regardless of the pressure of a vapor fuel G. When the moving core 10 and the permanent magnet 19 are mutually repulsed, in the case where the pressure of the vapor fuel becomes higher than the sum of repulsive force and the pushing force of the coil spring 17, the canister passage opens. In the case of nonapplying the electric current, when the pressure of the vapor fuel G becomes higher than the sum of the pushing forces of the coil springs 11, 17, the canister passage opens.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an evaporated fuel control valve device arranged between a fuel tank and an evaporated fuel processing device (hereinafter referred to as a canister) for preventing the evaporated fuel of a vehicle from being released into the atmosphere. Regarding

[0002]

2. Description of the Related Art As a part of the protection of the natural environment, strict leakage control is obligatory for evaporated fuel and evaporative emission released from the fuel system of a vehicle such as a fuel tank or carburetor into the atmosphere. The evaporative fuel control valve device disclosed in Japanese Utility Model Laid-Open No. 4-125655 has a canister passage communicating with a canister and a fuel tank passage communicating with a fuel tank, as shown in FIG. Two
And a constant pressure actuating valve and a differential pressure actuating valve are provided in each communicating passage, and one end of a shaft capable of advancing and retracting is brought into contact with the diaphragm of the constant pressure actuating valve, and the other end side Is configured to be movable with respect to the solenoid when not energized and to support the shaft so as to compulsorily move in the valve opening direction when energized. Then, when the internal pressure of the fuel tank exceeds a predetermined value, the constant pressure operating valve opens and the evaporated fuel flows to the canister. Also, the differential pressure operated valve is
Only when the internal pressure of the canister becomes higher than the internal pressure of the fuel tank and the difference exceeds a predetermined value, the second communication passage is opened to allow the evaporated fuel to flow to the fuel tank.

[0003]

However, the above vaporized fuel control valve device compels a constant pressure operating valve of a known 2-way valve incorporating a constant pressure operating valve and a differential pressure operating valve even under a closed condition. Since the function as a solenoid valve that can be opened dynamically is added, there is a problem that not only the structure becomes complicated, but also the number of work steps in assembling manufacturing increases and the cost increases. Incidentally, JP-A-3-204
The electromagnetic switching valve disclosed in Japanese Patent No. 487 and Japanese Patent Application Laid-Open No. 4-29685 switches the inflowing hot water to either one of the flow paths in two directions and supplies the hot water. It cannot be used as a fuel vapor control valve that is required to open under low pressure, high pressure, and three types of valve opening conditions regardless of pressure. The present invention has been made to solve the above problems, and an object thereof is to provide an evaporated fuel control valve device having a simple structure that can be opened under the valve opening conditions of the above-described three modes.

[0004]

In order to achieve the above object, an evaporated fuel control valve device of the present invention according to claim 1 communicates with a first passage into which evaporated fuel is introduced and the first passage. And a second passage connected to the evaporated fuel processing device,
An electromagnetic solenoid, a moving core magnetized by energizing the electromagnetic solenoid to form a magnetic pole and attracted, and a valve body fixed to a diaphragm and arranged to face the moving core to open and close the second passage, The moving core is composed of a magnetic body fixed to a surface of the valve body facing the moving core and an elastic member for pressing the moving core toward the magnetic body. The energizing member resists the elastic force of the elastic member when energized. The moving core is attracted by the moving core and the magnetic body by changing the energizing direction and changing the magnetic pole formed on the facing surface of the moving core with respect to the magnetic body. In this case, the moving core and the magnetic body repel each other and the pressure of the evaporated fuel exceeds the repulsive force. And if the opening time was, and characterized in that a third aspect of the case that opens when the pressure of the fuel vapor than the elasticity of the non-energized time of the elastic member exceeds.

According to a second aspect of the present invention, there is provided an evaporated fuel control valve device according to the first aspect, wherein the valve element includes an elastic member that acts in a direction of closing the second passage. The relative position relationship between the moving core and the magnetic body is controlled by adjusting the elastic coefficients of the elastic member and the elastic member that presses the moving core toward the magnetic body. Characterize.

In order to achieve the above object, an evaporated fuel control valve device according to a third aspect of the present invention is characterized in that, in the structure according to the first and second aspects, the magnetic body and the valve body are integrally formed. Characterize.

[0007]

According to the evaporated fuel control valve device of the present invention as set forth in claim 1, when the electromagnetic solenoid is energized,
The moving core is attracted against the elastic force of the elastic member, and the magnetic pole formed on the facing surface of the moving core changes according to the energizing direction. The second passage opens when the moving core and the magnetic substance are adsorbed regardless of the pressure of the evaporated fuel, and when the moving core and the magnetic substance repel, it opens when the pressure of the evaporated fuel exceeds the repulsive force. Further, when the pressure of the evaporated fuel exceeds the elastic force of the elastic member when de-energized, it opens. Therefore, it is suitable as an evaporated fuel control valve device that is required to be opened when the pressure of the evaporated fuel is low, high, and under three valve opening conditions regardless of the pressure. Further, since the elastic member, the moving core, the magnetic body, and the valve body are arranged in series on the central axis, there is an effect that the entire device can be compactly made compact and lightweight.

According to the fuel vapor control valve device of the present invention as defined in claim 2, the elastic member for causing the valve element to act in the direction of closing the second passage and the elastic member for pressing the moving core in the direction of the magnetic substance. Since the relative positional relationship between the moving core and the magnetic body is controlled by adjusting the elastic modulus of each member, the pressure at low pressure and the pressure at high pressure of the evaporated fuel, which is the valve opening condition, can be set to predetermined values. There is an effect that a stable function can be exhibited as the fuel control valve device.

According to the fuel vapor control valve device of the present invention as defined in claim 3, since the magnetic body and the valve body are integrated, the number of parts can be reduced and the number of assembling steps can be reduced.

[0010]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows an outline of an evaporated fuel control system 100 using an evaporated fuel control valve device 1 according to the present invention. The fuel vapor control valve device 1 includes a fuel tank 101 and a canister 102.
Is inserted in the pipe 103 for connecting. Canister 10
2 is connected to an intake pipe 105 of the engine via a purge control valve 104. The evaporated fuel control system 100 uses the evaporated fuel G generated in the fuel tank 101.
To operate the evaporative fuel control valve device 1 to activate the canister 10
The intake pressure of the engine is used to perform the purge by opening the purge control valve 104 according to the load condition of the engine and opening and closing the purge control valve 104.

FIG. 2 is a sectional view of the evaporated fuel control valve device 1. The electromagnetic solenoid 2 is composed of a coil 3, a yoke 4, and a stator core 5 fixed to the center of the coil 3. The stator core 5 has a tubular shaft shape in which a central shaft hole 6 is formed, and a filter 8 is fixed to an upper end of the reduced diameter portion 7 protruding from the electromagnetic solenoid 2. An enlarged diameter portion 9 is formed in the central shaft hole 6. The moving core 10 is arranged so as to face the stator core 5. Moving core 10
The coil spring 11 is hooked on the spring hooking recess 10a formed in the above and the enlarged diameter step portion 9a of the enlarged diameter portion 9.

Below the electromagnetic solenoid 2, a frame 12 is formed integrally with the frame 3a of the coil 3. A lower frame 13 is fixed to the frame 12. The lower frame 13 has a fuel tank passage (first passage) 14 connected to the fuel tank 101, and the fuel tank passage 1
A canister passage (second passage) 15 that is connected to the canister 102 is formed orthogonal to 4. further,
A diaphragm 16 is stretched by the frame 12 and the lower frame 13. A coil spring 17 is hung between the upper surface of the diaphragm 16 and the lower surface of the frame 12. A valve element 18 is fixed to the center of the diaphragm 16 and opens and closes the canister passage 15 to open the fuel tank passage 14
Connect and disconnect with. A permanent magnet 19 having magnetic poles formed in the axial direction is fixed to the valve body 18 and faces the moving core 10.

The operation of the evaporated fuel control valve device 1 having the above-mentioned structure will be described below. (1) When the vehicle is stopped and de-energized When the vehicle is stopped and de-energized, the elastic force of the coil spring 11 causes the moving core 10 to contact the permanent magnet 19 to press the valve body 18 as shown in FIG.
The diaphragm 16 is pressed by the elastic force of. Therefore,
The valve body 18 closes the upper surface opening of the canister passage 15 and cuts off the communication with the fuel tank passage 14. When the vehicle is stopped, the fuel tank 101 is normally sealed, so that the internal pressure of the fuel tank 101 may increase due to temperature rise or the like. The internal pressure of the fuel tank 101 increases and the diaphragm 16
When the force acting on the valve exceeds the sum of the pressing force of the coil spring 11 acting on the valve body 18 and the pressing force of the coil spring 17, the valve body 18 is pushed up and the fuel tank passage 14 and the canister passage 15 communicate with each other. As a result, the vaporized fuel G whose pressure has increased flows through the canister passage 15 and the canister 1
Adsorbed on 02. Then, when the internal pressure of the fuel tank 101 decreases, the valve body 18 closes the canister passage 15. As described above, the evaporated fuel control valve device 1 has a function of a high pressure fuel tank internal pressure valve (constant pressure valve) when the vehicle is stopped and de-energized.

(2) During running (when energized) As shown in FIG. 3, during running, the electromagnetic solenoid 2 is energized, and the moving core 10 resists the elasticity of the coil spring 11.
Aspirate. Then, at this time, the energizing direction is set so that the magnetic poles formed on the moving core 10 are the same magnetic poles on the surfaces of the moving core 10 and the permanent magnet 19 that face each other. As a result, the moving core 10 and the permanent magnet 19 repel each other, and the repulsive force and the pressing force of the coil spring 17 cause the valve body 18 to move to the canister passage 15.
Of the fuel tank passage 14 is blocked by closing the upper opening of the. Here, when the internal pressure of the fuel tank 101 acting on the diaphragm 16 exceeds the sum of the repulsive force and the pressing force of the coil spring 17, the valve body 18 is pushed up and the fuel tank passage 14 and the canister passage 15 communicate with each other. .

In this case, the coil spring 1 is stronger than the repulsive force.
By setting the spring constant of the coil spring 11 so that the pressing force of 1 becomes large, the evaporated fuel control valve device 1
It has the function of a low-pressure fuel tank internal pressure valve (constant pressure valve) that operates when the internal pressure of the fuel tank 101 is lower than when the vehicle is stopped and when the power is not supplied. As a result, the evaporated fuel G in the fuel tank 101 is guided to the canister 102, the purge control valve 104 is opened / closed according to the load condition of the engine, and the intake pressure of the engine is used for purging.

(3) During refueling During refueling, the electromagnetic solenoid 2 is energized in the direction opposite to the energizing direction during traveling. As shown in FIG. 4, the coil spring 11
The moving core 10 and the permanent magnet 19 that are attracted against the elastic force of the magnet are attracted and integrated, and the valve body 18 is pulled up against the elastic force of the coil spring 17 to force the fuel tank passage 14 and the canister passage 15. Communicate with. Therefore, at the time of refueling, the fuel tank 101 that communicates with the canister 102
It is possible to reduce the internal pressure of the fuel cell, reduce the refueling resistance, and prevent the evaporated fuel G during refueling from being released from the refueling port to the atmosphere.

In the above embodiment, the power of the electromagnetic solenoid 2, the strength of the magnetic force of the permanent magnet 19 and the coil spring 11 are used.
By adjusting the spring constants of the coil spring 17 and the coil spring 17, the pressure when functioning as a high-pressure fuel tank internal pressure valve and the pressure when functioning as a low-pressure fuel tank internal pressure valve are set to predetermined pressures for both high and low conditions. The operation of the constant pressure valve can be stabilized. Further, by integrating the valve element 18 and the permanent magnet 19, there are advantages that the number of parts can be reduced, the cost can be reduced, and the assembling work can be made efficient.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an evaporated fuel control system.

FIG. 2 is a cross-sectional view of the evaporated fuel control valve device when the vehicle is stopped and de-energized.

FIG. 3 is a cross-sectional view of a main part showing an operation of the evaporated fuel control valve device during traveling.

FIG. 4 is a cross-sectional view of an essential part showing the operation of the fuel vapor control valve device during refueling.

[Explanation of symbols]

 1 Evaporative Fuel Control Valve Device 2 Electromagnetic Solenoid 10 Moving Core 11, 17 Coil Spring 14 Fuel Tank Passage (First Passage) 15 Canister Passage (Second Passage) 16 Diaphragm 18 Valve Body 19 Permanent Magnet (Magnetic Body) 102 Canister G Evaporative fuel

Claims (3)

[Claims] 1. A first passage through which evaporated fuel is introduced, a second passage communicating with the first passage and connected to an evaporated fuel processing device, an electromagnetic solenoid, and energization of the electromagnetic solenoid. Magnetized to form a magnetic pole and attracted, a valve body fixed to a diaphragm and arranged to face the moving core to open and close the second passage, and a facing surface of the valve body to the moving core. It is composed of a magnetic body fixed to the magnetic core and an elastic member that presses the moving core toward the magnetic body.When energized, the moving core is attracted against the elasticity of the elastic member and the energizing direction is changed. By changing the magnetic pole formed on the facing surface of the moving core with respect to the magnetic body, the moving core and the magnetic body are opened in a manner in which the second passage is opened. When it is worn and opened regardless of the pressure of the evaporated fuel, when it is opened when the moving core and the magnetic body repel and the pressure of the evaporated fuel exceeds the repulsive force, and when the elastic member is not energized The evaporated fuel control valve device is characterized in that it has three modes of opening when the pressure of the evaporated fuel exceeds the pressure of the evaporated fuel. 2. An elastic member that acts in the direction in which the valve body closes the second passage is provided, and the elastic coefficients of the elastic member and the elastic member that presses the moving core toward the magnetic body are adjusted. Thus, the evaporated fuel control valve device according to claim 1, wherein the relative positional relationship between the moving core and the magnetic body is controlled. 3. The evaporated fuel control valve device according to claim 1, wherein the magnetic body and the valve body are integrally formed.