WO2013018142A1

WO2013018142A1 - Airtight diagnostic device

Info

Publication number: WO2013018142A1
Application number: PCT/JP2011/004400
Authority: WO
Inventors: 中川　聡
Original assignee: 三菱電機株式会社
Priority date: 2011-08-03
Filing date: 2011-08-03
Publication date: 2013-02-07

Abstract

A spiral guide wall (36) is provided upright and a spiral flow channel is formed in a space created by a second housing (28) and a partition wall (31) of a third housing (29), and a groove (38) is formed on a bottom surface of the flow channel. As a gas entering an inlet (30) from an air pump (13) flows through the spiral flow channel and exits toward a check valve (14) from an outlet (32), foreign matter included in the gas is separated out under the force of gravity. Having been separated out, the foreign matter accumulates in the groove (38), and does not flow back into the flow channel.

Description

Airtightness diagnostic device

The present invention relates to an airtightness diagnosis device that diagnoses leakage by utilizing pressure fluctuations in automobile piping.

There is an air-tightness diagnostic apparatus that pressurizes (or depressurizes) a piping system for evaporative gas (vaporized fuel) recovery installed in an automobile and diagnoses leakage of the piping system based on subsequent pressure behavior (for example, Patent Document 1). reference). If a check valve is installed on this pipe, it is possible to easily maintain a pressurized (or depressurized) state in a space-saving and cost-saving manner during airtightness diagnosis (see, for example, Patent Document 2).

Japanese translation of PCT publication No. 8-505918 JP 2005-54686 A

In the case of a configuration in which the piping system is depressurized by an air pump and the depressurized state is maintained by a check valve installed on the downstream side of the air pump as in Patent Document 2, foreign matter such as wear powder and dust flowing out from the air pump There is a problem that the operation of the check valve is hindered and the sealing performance is deteriorated.
On the other hand, when a check valve is installed on the upstream side of the air pump, gas leaks from the air pump itself, and this leakage countermeasure is costly.

The present invention has been made to solve the above-described problems, and has an object to prevent foreign matters from flowing into the check valve and prevent the performance of the check valve from deteriorating.

An airtightness diagnosis apparatus according to the present invention includes an air pump that changes the internal pressure of an evaporation gas processing system, a foreign matter separation mechanism that is integrally provided on the discharge side of the air pump and separates foreign matter contained in gas discharged from the air pump, and foreign matter And a check valve provided integrally on the outlet side of the separation mechanism.

According to the present invention, since foreign matter contained in the gas discharged from the air pump is separated by the foreign matter separation mechanism and then flows to the check valve, the foreign matter can be prevented from flowing into the check valve and the check valve performance can be prevented from being deteriorated. be able to.

It is a figure which shows the structure of the evaporation gas processing system to which the airtight diagnostic apparatus which concerns on Embodiment 1 of this invention is applied. It is sectional drawing which shows the structure of the non-return valve integrated air pump among the airtight diagnosis apparatuses which concern on Embodiment 1. FIG. FIG. 3 is a plan view showing a configuration of a foreign matter separation space of the check valve-integrated air pump in the first embodiment. It is sectional drawing which shows the structure of the non-return valve integrated type air pump among the airtight diagnosis apparatuses concerning Embodiment 2 of this invention. 6 is a plan view showing a configuration of a foreign matter separation space of a check valve-integrated air pump according to Embodiment 2. FIG. It is sectional drawing which shows the structure of the non-return valve integrated type air pump among the airtight diagnosis apparatuses concerning Embodiment 3 of this invention. 6 is a plan view showing a configuration of a foreign matter separation space of a check valve-integrated air pump according to 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.
The evaporative gas processing system shown in FIG. 1 includes a fuel tank 1, a canister 2 that adsorbs and temporarily accumulates the evaporative gas in the fuel tank 1, an intake manifold 3 that introduces the evaporative gas collected in the canister 2 to the engine, and an evaporative gas amount. And a purge solenoid valve 4 for controlling. The airtightness diagnostic apparatus 10 according to the first embodiment is a product used for detecting leakage in the piping system 5 indicated by a thick line in FIG. 1 and closes the pipe that communicates the canister 2 with the atmosphere side. A vent solenoid valve 11 and a check valve-integrated pump 12 for leading the atmosphere from the atmosphere side to the canister 2 and pressurizing the piping system 5 are provided.

The check valve integrated pump 12 includes an air pump 13 that discharges gas from the atmosphere side to the canister 2 to pressurize the piping system 5, a check valve 14 provided on the discharge side of the air pump 13, the air pump 13, and the check valve. A foreign matter separation mechanism 15 that is formed integrally with the valve 14 and separates foreign matter such as wear powder and dust contained in the gas discharged from the air pump 13 is provided.

FIG. 2 is a cross-sectional view of the check valve integrated pump 12, and FIG. 3 is a plan view of the foreign matter separating mechanism 15.
A vane pump is used as the air pump 13. The air pump 13 is fixed to the first housing 23 with a metal plate 24 sandwiched between a rotor 22 that rotates a plurality of blades 21, a resin-made first housing 23 that houses the rotor 22, and the rotor 22 is driven to rotate. And a motor 25. The first housing 23 is provided with an intake port 26 that communicates with the atmosphere side and takes in the atmosphere, and a first filter 27 is attached to the first housing 23.

The bottom side of the first housing 23 is closed by a second housing 28 that is a resin plate-like component, and a third housing 29 that is a resin-made cylindrical component is attached. The second housing 28 and the third housing 29 are fastened to the metal plate 24 together with the first housing 23 by screws (not shown).

A gas inlet 30 is opened in the second housing 28, and a gas outlet 32 is opened in the partition wall 31 of the third housing 29 to communicate between the air pump 13 and the check valve 14. The foreign matter separating mechanism 15 is configured in a space surrounded by the second housing 28 and the partition wall 31 of the third housing 29. Further, the outer side of the partition wall 31 is an exhaust port 33 communicating with the canister 2, and a second filter 34 is attached thereto. Further, an O-ring 35 is installed on the outer peripheral surface of the third housing 29. When the check valve integrated pump 12 is incorporated in a case (not shown), the gap with the case is closed, and the exhaust port The leakage of the gas led out from 33 to the canister 2 side into the case is prevented.

In the foreign matter separating mechanism 15, a spiral guide wall 36 is erected from the partition wall 31 of the third housing 29. Since the flow path connecting the gas inlet 30 and the outlet 32 is stretched by the spiral guide wall 36 and has a labyrinth structure, a sufficient flow path length for separating foreign substances can be secured. In the example of FIG. 3, a spiral flow path having a total of two rounds, one round on the outer circumferential side and one round on the inner circumferential side, is formed inside the third housing 29, but is not limited thereto.
In addition, a plurality of partition plates 37 that block the lower side of the flow path are erected, and foreign substances separated by their own weight are stored in grooves 38 sandwiched between the partition plates 37. As a result, the foreign matter once separated does not enter the flow path again, and the foreign matter separated in the groove 38 can be held until the product is discarded. Furthermore, since foreign matter does not accumulate on the flow path, the influence on the flow rate of the air pump 13 due to the accumulation of foreign matter can be minimized.

The shaft end portion of the check valve 14 penetrates and is engaged with the partition wall 31 of the third housing 29. The umbrella-type valve element of the check valve 14 is located in the exhaust port 33 and closes the outlet 32 when pressure is applied from the canister 2 side. Since the foreign matter is separated from the gas discharged from the outlet 32 to the exhaust port 33 by the foreign matter separation mechanism 15, it is possible to prevent the check valve 14 from being hindered by the foreign matter and maintain the sealing performance.

At the time of airtightness diagnosis, the canister vent solenoid valve 11 is closed, and the air pump 13 is operated with the flow path connecting the atmosphere side and the piping system 5 side closed. In the check valve integrated pump 12, the air is sucked from the atmosphere side to the intake port 26 by the rotation of the blade 21 and is discharged to the inlet 30. The gas flowing into the foreign matter separation mechanism 15 from the inlet 30 flows through the labyrinth flow path along the spiral guide wall 36, and the foreign matter is separated and exits from the outlet 32. And it is derived | led-out from the exhaust port 33 to the canister 2 side, and the piping system 5 is pressurized. The internal pressure of the piping system 5 is monitored by a pressure sensor (not shown), and the air pump 13 is stopped by increasing the pressure to a predetermined pressure. At this time, since the pressure on the exhaust port 33 side communicating with the canister 2 is higher than the pressure on the foreign matter separation mechanism 15 side, the check valve 14 closes the outlet 32 due to the pressure difference, and the pressurized state of the piping system 5 Hold. If the internal pressure of the piping system 5 drops below a predetermined threshold while maintaining the pressurized state after the air pump 13 is stopped, it is diagnosed that a leak has occurred.

For the convenience of the shape of the groove 38 provided in the foreign matter separating mechanism 15, when the check valve integrated pump 12 is installed with the drive motor 25 up and the exhaust port 33 down as shown in FIG. The foreign matter separation effect is the highest. However, even if it is installed in an inclined state, the groove 38 has a certain depth, so that the foreign matter once separated can be stored in the groove 38 and has a foreign matter separating effect.

As described above, according to the first embodiment, the air tightness diagnosis device is integrally provided on the air discharge side of the air pump 13 and the air pump 13 that discharges and pressurizes the atmosphere to the piping system 5 of the evaporation gas processing system. The foreign matter separating mechanism 15 for separating foreign matter contained in the atmosphere discharged from the air and the check valve 14 provided integrally on the outlet 31 side of the foreign matter separating mechanism 15 are further provided. A configuration having a groove 38 was adopted. For this reason, the inflow of foreign matter into the check valve 14 can be prevented, and the performance degradation of the check valve 14 can be prevented. Therefore, the check valve integrated pump 12 in which the reliability of the check valve 14 is improved can be provided.

Embodiment 2. FIG.
FIG. 4 is a cross-sectional view of the check valve integrated pump 12 according to Embodiment 2 of the present invention. FIG. 5 is a plan view showing the configuration of the foreign matter separating mechanism 15. 4 and 5, the same or corresponding parts as those in FIGS. 2 and 3 are denoted by the same reference numerals and description thereof is omitted.
In the second embodiment, in order to further enhance the foreign matter separation effect of the foreign matter separation mechanism 15, a small size is provided at the rear part of the labyrinth flow path constituted by the inner wall surface of the third housing 29 and the spiral guide wall 36. A filter 40 is installed. This filter 40 separates minute foreign matter that has not been separated by its own weight in the labyrinth flow path. At this time, since the foreign substance having a large particle size has already been separated upstream, the life of the filter 40 can be extended. Further, foreign matter accumulates on the filter 40, but the entire space in which the filter 40 is installed becomes a flow path. Therefore, it is possible to prevent a decrease in the flow rate of the air pump 13 due to clogging by taking a large cross-sectional area of the flow path. It becomes possible.
For example, a sponge filter is used as the filter 40.

The foreign matter separation mechanism 15 of the second embodiment is merely a change in the internal structure of the third housing 29 from the foreign matter separation mechanism 15 of the first embodiment. Therefore, the shape can be changed relatively easily by simply removing the screw and rearranging the third housing 29.

As described above, according to the second embodiment, the foreign matter separation mechanism 15 includes the spiral flow path that communicates the air pump 13 and the check valve 14, the foreign matter reservoir groove 38 provided in the flow path, The filter 40 is provided at the outlet 32 on the check valve 14 side of the flow path. For this reason, the foreign matter separation effect can be enhanced, the foreign matter can be prevented from flowing into the check valve 14, and the performance degradation of the check valve 14 can be prevented. Therefore, the check valve integrated pump 12 in which the reliability of the check valve 14 is further improved can be provided.

Embodiment 3 FIG.
FIG. 6 is a cross-sectional view of the check valve-integrated pump 12 according to Embodiment 3 of the present invention. FIG. 7 is a plan view showing the configuration of the foreign matter separating mechanism 15. 6 and FIG. 7, the same or equivalent parts as those in FIG. 2 and FIG.
In the third embodiment, when the foreign matter such as abrasion powder generated by the air pump 13 is small, the foreign matter separating mechanism 15 is not provided with the spiral guide wall 36 and the partition plate 37, and only the filter 50 is provided. The filter 50 separates gaseous foreign substances flowing from the inlet 30 to the outlet 32.

In the case of this configuration, the space constituting the foreign matter separation mechanism 15 is a simple cylindrical space, without adding a complicated new structure such as a spiral guide wall 36 and a partition plate 37, and with a simple filter. 50 can be installed. Therefore, it can be manufactured easily and the product cost can be reduced. Further, in this configuration, the entire interior of the third housing 29 becomes a flow path, so that it is possible to prevent a decrease in the flow rate of the air pump 13 due to clogging by taking a large cross-sectional area of the flow path.
For example, a sponge filter is used as the filter 50.

The foreign matter separation mechanism 15 of the third embodiment is merely a change in the internal structure of the third housing 29 from the foreign matter separation mechanism 15 of the first and second embodiments. Therefore, the shape can be changed relatively easily by simply removing the screw and rearranging the third housing 29.

As described above, according to the third embodiment, the foreign matter separation mechanism 15 is configured to have the filter 50 installed in the flow path that connects the air pump 13 and the check valve 14. For this reason, the inflow of foreign matter into the check valve 14 can be prevented, and the performance degradation of the check valve 14 can be prevented. Therefore, the check valve integrated pump 12 in which the reliability of the check valve 14 is improved can be provided.

In the first to third embodiments, the configuration of the airtightness diagnosis apparatus 10 has been described by taking as an example the case where the airtightness diagnosis is performed by pressurizing the piping system 5 of the evaporation gas processing system. Thus, the airtightness diagnosis apparatus 10 can also be applied when performing airtightness diagnosis.
In the case of pressurization, as described above, the intake port 26 of the check valve-integrated pump 12 is communicated with the atmosphere side, and the exhaust port 33 is communicated with the canister 2 side. The intake port 26 of the stop valve-integrated pump 12 is communicated with the canister 2 side, and the exhaust port 33 is communicated with the atmosphere side. At the time of airtightness diagnosis, the piping system 5 is decompressed by sucking the gas on the canister 2 side with the air pump 13. The gas sucked by the air pump 13 flows through the foreign matter separation mechanism 15 and is led out from the discharge port 33 on the check valve 14 side to the atmosphere side. When the air pump 13 is stopped, the pressure on the exhaust port 33 side communicating with the atmosphere side is higher than the pressure on the foreign matter separation mechanism 15 side communicating with the canister 2, so the check valve 14 closes the outlet 32 due to the pressure difference. The decompression state of the piping system 5 is maintained. If the internal pressure of the piping system 5 rises above a predetermined threshold while maintaining the reduced pressure state after the air pump 13 is stopped, it is diagnosed that a leak has occurred.
Also in this configuration, foreign matter contained in the gas discharged from the air pump 13 is separated by the foreign matter separation mechanism 15 and then flows to the check valve 14, so that foreign matter can be prevented from flowing into the check valve 14. 14 performance degradation can be prevented.

In the present invention, within the scope of the invention, any combination of each embodiment, any component of each embodiment can be modified, or any component can be omitted in each embodiment. .

As described above, the airtightness diagnostic apparatus according to the present invention detects foreign matter in an automobile evaporative gas processing system because the foreign matter is separated between the air pump and the check valve to improve the reliability of the check valve. It is suitable for use in an airtight diagnosis device.

1. Fuel tank, 2. Canister, 3. Intake manifold, 4. Purge solenoid valve, 5. Piping system, 10. Airtightness diagnostic device, 11. Canister vent solenoid valve, 12. Check valve integrated pump, 13. Air pump, 14. Check valve, 15. Foreign matter. Separation mechanism, 21 blades, 22 rotor, 23 first housing, 24 metal plate, 25 drive motor, 26 intake, 27 first filter, 28 second housing. 29 3rd housing, 30 inlet, 31 partition, 32 outlet, 33 outlet, 34 second filter, 35 O-ring, 36 spiral guide wall, 37 partition plate, 38 groove, 40, 50 filter.

Claims

In the gas tightness diagnostic device that changes the internal pressure of the vapor gas processing system that collects the vapor generated in the fuel tank and introduces it into the engine, and then diagnoses the gas tightness by the pressure fluctuation,
An air pump for changing the internal pressure of the evaporation gas processing system;
A foreign matter separating mechanism that is integrally provided on the discharge side of the air pump and separates foreign matter contained in the gas discharged from the air pump;
An airtightness diagnosis apparatus comprising: a check valve provided integrally on an outlet side of the foreign matter separation mechanism.
2. The airtightness diagnosis apparatus according to claim 1, wherein the foreign matter separation mechanism has a spiral flow path communicating with the air pump and the check valve.
3. The airtightness diagnosis apparatus according to claim 2, wherein the foreign matter separation mechanism has a foreign matter storage groove provided in a spiral flow path.
2. The airtightness diagnosis apparatus according to claim 1, wherein the foreign matter separation mechanism has a filter installed in a flow path communicating with the air pump and the check valve.