WO2017006463A1

WO2017006463A1 - Check valve and purge solenoid valve equipped with check valve

Info

Publication number: WO2017006463A1
Application number: PCT/JP2015/069659
Authority: WO
Inventors: 中川　聡
Original assignee: 三菱電機株式会社
Priority date: 2015-07-08
Filing date: 2015-07-08
Publication date: 2017-01-12

Abstract

A check valve (7) is configured so as to be equipped with: a valve body (15) that opens/closes a flow path communicating with a purge pipe (5); a spring (17) that presses the valve body (15) in the direction for closing the flow path; and an air damper structure (13) that generates attenuation force in the opening/closing directions with respect to the valve body (15). Thus, it is possible to prevent following movement of the check valve (7) in response to pressure pulsation generated by duty driving of a purge solenoid valve (6), and it is possible to prevent unnecessary opening/closing operations of the check valve (7). Furthermore, attenuation force from the air damper structure (13) is applied to the closing force of the spring (17) when vibration occurs, so the load on the spring (17) can be reduced, and valve-opening performance of the check valve (7) at the time of a low pressure differential can be improved.

Description

Check valve and purge solenoid valve with check valve

The present invention relates to a check valve used in a transpiration gas treatment system of a gasoline vehicle and a purge solenoid valve with a check valve.

Gasoline automobiles are equipped with a transpiration gas treatment system for the purpose of preventing the transpiration gas evaporated in the gasoline tank from flowing into the atmosphere. The transpiration gas treatment system controls the flow rate of the transpiration gas flowing through the canister, which has a built-in activated carbon for adsorbing the transpiration gas, the purge pipe connecting the canister and the intake manifold (hereinafter referred to as intake manifold) pipe of the engine, and the purge pipe. And a purge solenoid valve.

The air containing the vaporized gas evaporated in the gasoline tank is released to the atmosphere through the canister. At that time, the vaporized gas is adsorbed by the activated carbon in the canister, and only clean air is released to the atmosphere. The
Further, the vaporized gas accumulated in the canister is separated from the activated carbon by being sucked by the negative pressure generated in the intake manifold when the engine is operated, and flows into the engine through the purge pipe and is disposed of for combustion.

Normally, intake manifold negative pressure acts on the transpiration gas treatment system, and the transpiration gas flows from the canister to the intake manifold piping through the purge piping. However, in a turbocharged vehicle, positive pressure may be generated in the intake manifold due to turbocharging. In such a case, there is a concern that the transpiration gas flows back through the purge pipe, and the transpiration gas that flows backward flows out from the canister . In order to prevent this, a check valve for preventing the backflow of the purge pipe is installed in the transpiration gas processing system of a turbocharger-equipped vehicle (see, for example, Patent Documents 1 and 2).

JP 2014-227972 A JP 2013-15106 A

In the transpiration gas processing system as described above, the purge solenoid valve controls the flow rate of the transpiration gas flowing through the purge pipe by valve opening time control that is duty-driven at a driving frequency of about 10 Hz. At this time, pressure pulsation is generated in the purge pipe by opening and closing the valve body of the purge solenoid valve at high speed. Then, the check valve follows the pressure pulsation, and there is a problem that an unnecessary opening / closing operation is performed. As a result, the check valve collides with the seal surface many times, reducing the life of the check valve and generating noise due to the collision.

In addition, since the check valve is affected by engine vibration, the check valve is pressed against the seal surface using a high-load spring so as not to open even under vibration conditions of about 300 m / s ^2. There was a need. For this reason, the check valve cannot be opened at the time of a low differential pressure, the pressure loss increases, and there is a problem that the flow rate of the vaporized gas from the canister to the engine decreases.

The present invention was made to solve the above-described problems, and aims to suppress unnecessary opening / closing operations of the check valve and improve the valve opening performance of the check valve at the time of low differential pressure.

A check valve according to the present invention is a check valve installed in the same pipe as a duty-operated purge solenoid valve, and a valve body that opens and closes a flow path communicating with the pipe, and a valve body in a direction to close the flow path And a damper that generates a damping force in the opening / closing direction with respect to the valve body.

According to this invention, since the check valve includes the damper, the check valve can be prevented from following the pressure pulsation generated by the duty drive of the purge solenoid valve, and the check valve is unnecessary. Opening and closing operations can be suppressed. In addition, the damping force of the damper is added to the closing force of the spring as a force against the force in the valve opening direction caused by vibration, so the spring load can be reduced and the check valve opening performance at low differential pressure Can be improved.

It is a figure which shows the structural example of the transpiration | evaporation gas processing system using the non-return valve which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the structural example of the non-return valve which concerns on Embodiment 1, FIG. 2 (a) shows a valve opening state, FIG.2 (b) shows a valve closing state. It is a figure explaining the simple model of the non-return valve concerning Embodiment 1. FIG. It is sectional drawing which shows the structural example of the non-return valve which concerns on Embodiment 2 of this invention, Fig.4 (a) shows a valve opening state, FIG.4 (b) shows a valve closing state. 6 is a cross-sectional view showing an example in which a vent hole is formed in a valve body in a check valve according to Embodiment 2. FIG. It is sectional drawing which shows the structural example of the purge solenoid valve with a non-return valve concerning Embodiment 3 of this invention. FIG. 10 is a cross-sectional view showing a modification of the purge solenoid valve with check valve according to the third embodiment. It is a figure which shows the structural example of the transpiration | evaporation gas processing system which concerns on Embodiment 3. FIG.

Hereinafter, in order to explain the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration example of a transpiration gas treatment system using a check valve 7 according to Embodiment 1 of the present invention. The transpiration gas treatment system includes a canister 4 containing activated carbon that absorbs the transpiration gas evaporated in the gasoline tank 3, a purge pipe 5 that connects the canister 4 and the intake manifold pipe 1, and a flow rate of the transpiration gas that flows through the purge pipe 5. A purge solenoid valve 6 to be controlled and a check valve 7 to prevent backflow of the transpiration gas are provided. At the time of recovery of the transpiration gas, the air containing the transpiration gas evaporated in the gasoline tank 3 flows to the canister 4, the transpiration gas is adsorbed by the activated carbon in the canister 4, and only clean air is released to the atmosphere. During the treatment of the transpiration gas, the transpiration gas accumulated in the canister 4 is sucked by the negative pressure generated in the intake manifold pipe 1 downstream from the throttle valve 2, thereby passing through the canister 4, the purge pipe 5 and the intake manifold pipe 1. Then it flows into the engine and is disposed of by combustion.

2A and 2B are cross-sectional views illustrating a configuration example of the check valve 7 according to Embodiment 1, in which FIG. 2A shows a valve open state, and FIG. 2B shows a valve close state.
The check valve 7 is installed in the same purge pipe 5 as the duty solenoid purge solenoid valve 6. The check valve 7 includes a suction port 11 connected to the upstream side of the purge pipe 5, that is, the purge solenoid valve 6 side, and a discharge port 12 connected to the downstream side of the purge pipe 5, that is, the intake manifold pipe 1 side. Prepare. The suction port 11 and the discharge port 12 constitute a flow path communicating with the purge pipe 5, and the valve body 15 is installed in this flow path. Hereinafter, the direction in which the transpiration gas flows from the suction port 11 to the discharge port 12 is referred to as a flow forward direction A, and the direction in which the transpiration gas flows from the discharge port 12 to the suction port 11 is referred to as a reverse flow direction B.

The check valve 7 includes a valve body 15 that opens and closes a flow path that communicates with the purge pipe 5, a spring 17 that presses the valve body 15 in a direction that closes the flow path, and a damping force that opens and closes the valve body 15. And an air damper structure 13 for generating. An elastic body 18 is installed on the sealing surface of the suction port 11 against which the valve body 15 is pressed when the check valve 7 is closed. The elastic body 18 eliminates the gap between the valve body 15 and the sealing surface and prevents the leaked gas from leaking. The elastic body 18 may be installed on the valve body 15.

The air damper structure 13 includes a bottomed cylindrical cylinder 14 having an opening formed on the suction port 11 side, a valve body 15 accommodated inside the cylinder 14 so as to be slidable in the opening / closing direction, and the cylinder 14 and the valve body. And a damper chamber 16 formed by 15. In this air damper structure 13, the vaporized gas flowing through the flow path is caused to flow into and out of the damper chamber 16 through a gap where the cylinder 14 and the valve body 15 slide, thereby reducing the amount of vaporized gas. It has a damper function. In the configuration example of FIG. 1, a spring 17 is installed in the damper chamber 16.

The valve body 15 slides in the cylinder 14 in accordance with the pressure difference between the suction port 11 and the discharge port 12, and opens and closes the flow path. That is, when the intake manifold pipe 1 has a negative pressure and the discharge port 12 communicated with the intake manifold pipe 1 also has a negative pressure, the valve body 15 becomes a sealing surface of the suction port 11 as shown in FIG. The valve is opened and the transpiration gas in the flow forward direction A flows. On the contrary, when the intake manifold pipe 1 becomes positive pressure and the discharge port 12 communicating with the intake manifold pipe 1 also becomes positive pressure, the valve body 15 comes into contact with the sealing surface of the suction port 11 as shown in FIG. The valve is closed to prevent the transpiration gas from flowing in the reverse flow direction B.

Conventionally, when the purge solenoid valve 6 is driven with a duty, pressure pulsation is generated in the purge pipe 5, and the valve body 15 of the check valve 7 follows this pressure pulsation and performs an unnecessary opening / closing operation. As a result, the valve body 15 collides with the sealing surface many times, and there is a problem that the life of the check valve 7 is reduced and noise due to the collision occurs.
On the other hand, as shown in FIG. 1, the air damper structure 13 generates a damping force in the opening / closing direction with respect to the valve body 15, thereby suppressing unnecessary opening / closing operations. As a result, it is possible to suppress the reduction in the life of the check valve 7 and the generation of noise.

The check valve 7 using the spring 17 is advantageous in that it has high durability and is not easily affected by temperature change. On the other hand, the check valve 7 has a vibration magnitude so as not to open when vibration is applied from the outside. It was necessary to press the valve body 15 in the valve closing direction using the spring 17 having a corresponding load. Therefore, conventionally, in the case of the check valve 7 used in the transpiration gas treatment system, it is necessary to use a high-load spring 17 that does not open even under vibration conditions of about 300 m / s ² in consideration of engine vibration. It was. However, when the high-load spring 17 is used, the valve body 15 cannot be opened at a low differential pressure, the pressure loss in the check valve 7 increases, and the vaporized gas flow rate from the canister 4 to the engine decreases. It was.
On the other hand, as shown in FIG. 3 and formula (1), the air damper structure 13 generates a damping force in the opening / closing direction to hold the valve body 15, so that the load of the spring 17 is applied by the holding force of the air damper structure 13. Can be reduced. For this reason, the valve body 15 opens at a low differential pressure, and the pressure loss at the low differential pressure can be improved. Therefore, it is possible to minimize the decrease in the vaporized gas flow rate due to the addition of the check valve 7 to the purge pipe 5.

Here, F is a holding force for holding the valve body 15, c is a damping coefficient of the air damper structure 13, k is a spring constant of the spring 17, x is a displacement of the valve body 15, and t is time.

Further, the air damper structure 13 is composed of two parts, a bottomed cylindrical cylinder 14 and a valve body 15, and the number of additional parts is less than that of the conventional valve body 15. Therefore, there is an advantage that an increase in cost can be suppressed. The characteristics of the air damper structure 13 can be changed by the amount of transpiration gas flowing into and out of the damper chamber 16, and the change of the transpiration gas amount is adjusted by the size of the sliding gap between the cylinder 14 and the valve body 15. be able to. When the check valve 7 is used in a transpiration gas processing system, the size of the gap between the cylinder 14 and the valve body 15 may be adjusted so that the characteristics of the air damper structure 13 corresponding to the responsiveness required in the actual vehicle environment can be obtained. .

Note that if the desired amount of transpiration gas cannot be obtained only by the gap between the cylinder 14 and the valve body 15, the cylinder 14 may be formed with a vent hole 19 for allowing the transpiration gas to flow into and out of the damper chamber 16. In the configuration example of FIG. 1, a vent hole 19 is formed on the bottom surface of the cylinder 14 facing the discharge port 12. By adjusting the size of the vent hole 19, the characteristics of the air damper structure 13 can be easily changed.
The vent hole 19 may be formed in the valve body 15 instead of the cylinder 14.
The vent hole 19 is not necessary when a desired amount of transpiration gas can be ensured only by the gap between the cylinder 14 and the valve body 15.

As described above, according to the first embodiment, the check valve 7 includes the valve body 15 that opens and closes the flow path communicating with the purge pipe 5, the spring 17 that presses the valve body 15 in the direction of closing the flow path, and the valve body. Since the air damper structure 13 that generates the damping force in the opening / closing direction with respect to 15 is configured, it is possible to suppress the check valve 7 from following the pressure pulsation generated by the duty drive of the purge solenoid valve 6. Therefore, an unnecessary opening / closing operation of the check valve 7 can be suppressed. Further, since the damping force of the air damper structure 13 is added to the valve closing force of the spring 17 as a force against the valve opening direction force generated by vibration, the load of the spring 17 can be reduced, and the check valve at the time of low differential pressure 7 valve opening performance can be improved.

According to the first embodiment, the damper structure is the air damper structure 13 in which the valve body 15 is slidably accommodated in the opening and closing direction inside the cylinder 14 having an opening formed at one end thereof. Since there is a gap between the cylinder 14 and the valve body 15 that allows the flowing vaporized gas to flow into and out of the damper chamber 16 in the cylinder 14, the air damper structure 13 is simply configured. An increase in cost due to the addition can be suppressed. Further, by adjusting the gap between the cylinder 14 and the valve body 15, the characteristics of the air damper structure 13 can be changed. Alternatively, a vent hole 19 is formed in the cylinder 14 or the valve body 15 so that the vaporized gas flowing in the flow path flows into and out of the damper chamber 16 in the cylinder 14, and the size of the vent hole 19 is adjusted. Also, the characteristics of the air damper structure 13 can be changed.

Embodiment 2. FIG.
In the first embodiment, the damper structure is configured by the two parts of the cylinder and the valve body. However, in the second embodiment, the damper structure is configured by using a diaphragm.
4 is a cross-sectional view showing a configuration example of a check valve 7 according to Embodiment 2 of the present invention, in which FIG. 4 (a) shows a valve open state and FIG. 4 (b) shows a valve close state. The check valve 7 shown in FIG. 4 is installed in the same purge pipe 5 as the purge solenoid valve 6 in the transpiration gas processing system shown in FIG. In the following, FIG. 1 is used.

The check valve 7 according to the second embodiment includes a suction port 21 connected to the upstream side of the purge pipe 5 and a discharge port 22 connected to the downstream side of the purge pipe 5, and includes the suction port 11 and the discharge port. The valve body 25 is installed in the flow path constituted by 12.

Further, the check valve 7 according to the second embodiment has a valve body 25 that opens and closes a flow path communicating with the purge pipe 5, a spring 27 that presses the valve body 25 in a direction to close the flow path, and a valve body 25. And a diaphragm 23 as a damper structure for generating a damping force in the opening and closing direction. In addition, an elastic body 28 is installed on the sealing surface of the suction port 21 to which the valve body 25 is pressed when the valve is closed to prevent leakage of transpiration gas. The elastic body 28 may be installed on the valve body 25.

The damper structure of the second embodiment includes a diaphragm 23 to which the valve body 25 is fixed, and a vent hole 29 that allows outside air to flow into and out of the damper chamber 26 in the diaphragm 23. In the damper structure shown in FIG. 4, outside air is allowed to flow into and out of the damper chamber 26 in the diaphragm 23 from the vent hole 29, and the damper function is provided by reducing the amount of outside air. A spring 27 is installed in the damper chamber 26.

Even in the damper structure using the diaphragm 23, the check valve 7 is prevented from following the pressure pulsation generated by the duty drive of the purge solenoid valve 6, similarly to the air damper structure 13 of the first embodiment. It is possible to suppress an unnecessary opening / closing operation of the check valve 7. Further, as a force against the force in the valve opening direction generated by vibration, the damping force of the damper structure using the diaphragm 23 is added to the valve closing force of the spring 27, so that the load of the spring 27 can be reduced, and at the time of low differential pressure The valve opening performance of the check valve 7 can be improved.

In the first embodiment, if the gap between the cylinder 14 and the valve body 15 is reduced, the foreign body may be caught when the foreign substance flows in, and the valve body 15 may be fixed.
On the other hand, in the case of the damper structure using the diaphragm 23, the sliding gap of the valve body 25, that is, the gap between the valve body 25 and the case can be secured larger than the valve body 15 in the air damper structure 13. It becomes difficult to occur.

Further, in the first embodiment, it is difficult to make the gaps between the cylinder 14 and the valve body 15 the same between a plurality of devices, which may cause variations in the characteristics of the air damper structure 13 between the plurality of devices. .
On the other hand, in the case of a damper structure using the diaphragm 23, the amount of outside air flowing into and out of the damper chamber 26 in the diaphragm 23 depends only on the dimensions of the air holes 29, and therefore, characteristic variations among a plurality of devices. Can be made relatively small.

In the configuration example of FIG. 4, the outside air is taken into the damper chamber 26, but a structure may be adopted in which the vaporized gas flowing through the flow path is taken. An example of this structure is shown in FIG.
FIG. 5 is a cross-sectional view showing an example in which the vent hole 29 is formed in the valve body 25 in the check valve 7 according to the second embodiment. In this example, the valve body 25 fixed to the diaphragm 23 is formed with a vent hole 29 that allows the flow path and the damper chamber 26 to communicate with each other. The vaporized gas flowing in the flow path is caused to flow into and out of the damper chamber 26 from the vent hole 29, and the diaphragm 23 has a damper function by reducing the amount of vaporized gas.

Embodiment 3 FIG.
As described above, the check valve using the conventional spring has advantages such as high durability and being hardly affected by temperature change, but in order to prevent the valve from being opened when vibration is applied from the outside. There is a need to press the valve body in the valve closing direction with a spring load corresponding to the magnitude of vibration, and there is a problem that pressure loss increases in the check valve at low differential pressure depending on the vibration conditions of the mounting environment. In particular, a spring that requires a sufficient flow rate, such as a purge solenoid valve, but that is used under severe conditions, such as conditions where engine vibrations are applied, will greatly increase the pressure loss at low differential pressure. It was difficult to adopt a check valve using
In contrast, the check valves according to the first and second embodiments can reduce the load of the spring as much as the holding force by the damper structure is applied. Therefore, when compared under the same vibration conditions, the check valve according to

Embodiments

1 and 2 improves the pressure loss increase at the time of low differential pressure compared to the conventional check valve using a high-load spring. can do.
Therefore, without losing the merit of the check valve using the spring, the purge solenoid valve and the check valve that are used under conditions with severe vibration such as a transpiration gas treatment system are integrated into one component. It is possible.

FIG. 6 is a cross-sectional view showing a configuration example of a purge solenoid valve with a check valve according to Embodiment 3 of the present invention. The purge solenoid valve with check valve shown in FIG. 6 has a configuration in which the check valve 7 shown in FIG. 2 of the first embodiment is combined with the purge solenoid valve 6, and is the same as or corresponds to FIG. Parts are denoted by the same reference numerals and description thereof is omitted. In FIG. 6, the purge solenoid valve 6 and the check valve 7 are closed.

The purge solenoid valve with check valve according to the third embodiment includes a suction port 31 connected to the upstream side of the purge pipe 5, a discharge port 12 connected to the downstream side of the purge pipe 5, and a magnetic plunger 32. And a solenoid portion 33 that pulls the plunger 32 in the valve opening direction, and a spring 34 that presses the plunger 32 in the valve closing direction. A valve portion 35 having elasticity is attached to one end surface of the plunger 32. Further, a valve seat 36 that contacts the valve portion 35 is formed in the middle of the flow path from the suction port 31 to the discharge port 12, and the valve portion 35 contacts the valve seat 36 to close the valve portion 35. Opens away from the valve seat 36.

The solenoid unit 33 is composed of a coil and a core. The solenoid 33 generates an electromagnetic force in the core by energizing the coil, and the plunger 32 is pulled in the valve opening direction away from the valve seat 36. For example, the engine control unit (ECU) controls the energization of the solenoid unit 33 by pulse width modulation (PWM), and the purge solenoid valve 6 is duty-driven at a drive frequency of about 10 Hz, thereby reducing the valve opening time of the valve unit 35. Control. When the coil is not energized, the spring 34 presses the plunger 32 toward the valve seat 36 and closes the valve.

Further, the check valve 7 is disposed downstream of the valve seat 36 in the flow path extending from the suction port 31 to the discharge port 12. When the intake manifold pipe 1 has a negative pressure and the discharge port 12 communicated with the intake manifold pipe 1 also has a negative pressure, the valve body 15 of the check valve 7 opens, and the vaporized gas in the forward flow direction A flows. When the intake manifold pipe 1 becomes positive pressure and the discharge port 12 communicating with the intake manifold pipe 1 also becomes positive pressure, the valve body 15 of the check valve 7 is closed as shown in FIG. Stop.

Also, one purge solenoid valve 6 and two check valves 7 can be configured integrally.
FIG. 7 is a sectional view showing a modification of the purge solenoid valve with check valve according to Embodiment 3 of the present invention. FIG. 8 is a diagram showing a configuration example of a transpiration gas treatment system using the purge solenoid valve with a check valve shown in FIG.

In FIG. 8, a turbocharger compressor 8 is installed upstream of the throttle valve 2 of the intake manifold 1. The atmosphere taken in upstream of the intake manifold 1 is compressed by the compressor 8 and introduced into the engine through the throttle valve 2. Therefore, when the compressor 8 is operating, the intake manifold pipe 1 becomes a positive pressure due to the supercharged air, and it becomes difficult to suck the vaporized gas using the negative pressure. Therefore, during supercharging when the compressor 8 is operating, the vaporized gas of the canister 4 is caused to flow to the purge pipe 5, the purge solenoid valve 6, and the second pipe 5b using the negative pressure generated upstream of the compressor 8. Introduced into the engine. On the other hand, during non-supercharging when the compressor 8 is not operating, the vaporized gas of the canister 4 is caused to flow to the purge pipe 5, the purge solenoid valve 6, and the first pipe 5a using the negative pressure generated in the intake manifold pipe 1. Install into the engine.

A first check valve 7a and a first check valve 7a that prevent backflow are respectively connected to the first pipe 5a and the second pipe 5b that branch from the upstream position of the purge solenoid valve 6 in the purge pipe 5 and constitute a part of the purge pipe 5. 2 Check valve 7b is installed.
The purge solenoid valve with a check valve shown in FIG. 7 has a configuration in which the first check valve 7 a and the second check valve 7 b are integrated with the purge solenoid valve 6. Further, the purge pipe 5 is branched into a first pipe 5a and a second pipe 5b inside the purge solenoid valve with a check valve.

Specifically, as shown in FIG. 7, the purge solenoid valve with a check valve is connected to the suction port 31 connected to the upstream side of the purge pipe 5 and the first pipe 5 a on the downstream side of the purge pipe 5. The discharge port 12 of the first check valve 7a and the discharge port 12 of the second check valve 7b connected to the second pipe 5b on the downstream side of the purge pipe 5 are provided. In addition, a valve seat 36 that contacts the valve portion 35 is formed in the middle of the flow path communicating with the suction port 31, and the flow path is branched downstream of the valve seat 36 so that the first check valve 7a The discharge port 12 communicates with the discharge port 12 of the second check valve 7b.

During non-supercharging, when the purge solenoid valve 6 is opened, the vaporized gas in the canister 4 is discharged from the purge pipe 5, the suction port 31 of the purge solenoid valve 6, and the first check valve 7a due to the negative pressure of the intake manifold pipe 1. It flows into the intake manifold pipe 1 via the port 12 and the first pipe 5a, and is introduced into the engine.
On the other hand, at the time of supercharging, when the purge solenoid valve 6 is opened, the vaporized gas in the canister 4 is caused by the negative pressure on the upstream side of the compressor 8, thereby causing the purge pipe 5, the suction port 31 of the purge solenoid valve 6, and the second check valve. It flows to the upstream side of the compressor 8 via the discharge port 12 of the 7b and the second pipe 5b, and is introduced into the engine via the throttle valve 2.

6 and FIG. 7, the check valve 7 having the structure shown in FIG. 2 is combined with the purge solenoid valve 6. However, the structure shown in FIG. The check valve 7 may be combined.
Further, in the transpiration gas treatment system shown in FIG. 8, a purge solenoid valve with a check valve having the structure shown in FIG. 6 is installed on the first pipe 5a branched from the purge pipe 5, and also branched from the purge pipe 5. A purge solenoid valve with a check valve having the structure shown in FIG. 6 may be provided for the second pipe 5b.

As described above, according to the third embodiment, the purge solenoid valve 6 and the check valve 7 that are duty-driven are integrally formed. Therefore, the purge solenoid valve 6 and the check valve 7 are provided in the middle of the purge pipe 5. Compared with the case where each is installed, there are advantages such as reduction of parts such as a hose pipe connecting the purge pipe 5, the purge solenoid valve 6 and the check valve 7, and simplification of the vehicle body assembling work.

In the present invention, within the scope of the invention, free combinations of the respective embodiments, modification of arbitrary components of the respective embodiments, or omission of arbitrary components of the respective embodiments are possible.

Since the check valve according to the present invention is provided with a damper that generates a damping force in the opening / closing direction with respect to the valve body, it is suitable for use in a transpiration gas treatment system of a vehicle in which pressure pulsation and vibration occur. Yes.

1 intake manifold, 2 throttle valve, 3 gasoline tank, 4 canister, 5 purge piping, 5a first piping, 5b second piping, 6 purge solenoid valve, 7 check valve, 7a first check valve, 7b second reverse Stop valve, 8 compressor, 11, 21, 31 suction port, 12, 22 discharge port, 13 air damper structure, 14 cylinder, 15, 25 valve body, 16, 26 damper chamber, 17, 27 spring, 18, 28 elastic body, 19, 29 vent hole, 23 diaphragm (damper structure), 32 plunger, 33 solenoid part, 34 spring, 35 valve part, 36 valve seat, A flow forward direction, B reverse flow direction.

Claims

A check valve installed in the same piping as the purge solenoid valve driven by duty,
A valve body for opening and closing a flow path communicating with the pipe;
A spring that presses the valve body in a direction to close the flow path;
A check valve comprising: a damper that generates a damping force in the opening / closing direction with respect to the valve body.
The damper is an air damper in which the valve body is slidably accommodated in an opening / closing direction in a cylinder having an opening at one end, and the fluid flowing through the flow path flows into the cylinder and flows into the cylinder. The check valve according to claim 1, further comprising a gap between the cylinder and the valve body that flows out from the cylinder.
3. The check valve according to claim 2, wherein the cylinder or the valve body has a vent hole for allowing a fluid flowing through the flow path to flow into and out of the cylinder.
The damper is
A diaphragm to which the valve body is fixed;
The check valve according to claim 1, further comprising a vent hole for allowing outside air or a fluid flowing through the flow path to flow into and out of the diaphragm.
The check valve is a purge solenoid valve with a check valve installed in the same pipe as the duty solenoid purge solenoid valve,
The check valve is
A valve body for opening and closing the flow path of the purge solenoid valve;
A spring that presses the valve body in a direction to close the flow path;
A purge solenoid valve with a check valve, comprising: a damper that generates a damping force in the opening / closing direction with respect to the valve body.
The purge solenoid valve with a check valve according to claim 5, wherein the check valve and the purge solenoid valve are integrally formed.