JP2002213226A - Connection structure of gas recirculation hose of blow- by gas recirculation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effect further reliable introduction of outside air to a suction system through a gas recirculation hose dislocated from a connection part to a recirculation gas amount control valve. SOLUTION: A connection part 10 on the valve side of the gas recirculation hose 15 is cut obliquely based on its central axis and provided with a circular opening part 19a. When the gas recirculation hose 15 slips out and is dislocated from a hose connection part 13c of a PCV valve 13 mounted on an upper surface 12a of a cylinder head cover 12, the connection part 19 on the valve side is sucked to an upper surface 12a by a negative pressure introduced through a suction pipe 14. In this case, by sucking the connection part 19 on the valve side approximately in a vertical state to the upper surface 12a, an opening part 19a is opened to an external part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure of a recirculation hose in a blow-by gas recirculation device for recirculating blow-by gas inside an engine to an intake system in a vehicle.

[0002]

2. Description of the Related Art In recent years, in vehicles, an evaporative fuel purging device, an exhaust gas recirculating device, which is a device for purifying exhaust gas,
The blow-by gas recirculation device is also required to perform a self-diagnosis of its failure and functional deterioration. Of these, for the blow-by gas recirculation system that recirculates blow-by gas leaking into the crankcase of the engine main body to the intake system, the gas recirculation hose that returns blow-by gas from the engine main body to the intake system is disconnected, or during inspection. When forgetting to connect the gas recirculation hose, it is required to reliably detect the abnormal state and prevent the blow-by gas from being released into the outside air.

Conventionally, in a blow-by gas recirculation device,
As a method of detecting a leak based on a detachment of a gas recirculation hose, for example, there is a method performed by an abnormality detection device proposed in Japanese Patent Application Laid-Open No. 10-184335. In this abnormality detection device, the electronic control device that controls the operation of the engine is in an abnormal state when the ISC opening (load amount) of the idle speed (ISC) control valve during idling is smaller than the set opening. It is determined that there is. This is because if the gas recirculation hose is disconnected, outside air is introduced into the intake system from the opening and the intake air volume becomes larger than usual, so the ISC opening that is adjusted based on the intake air volume is abnormally small. It is based on being.

[0004]

As shown in FIG. 8, the gas recirculation hose 80 is connected to a hose connection part 83 of a recirculation gas amount control valve (PCV valve) 82 fixed to a cylinder head cover 81. Is usually the case. When the gas recirculation hose 80 comes off from the hose connection portion 83 of the PCV valve 82, as shown in FIG. 9, the gas recirculation hose 80 is sucked into the upper surface 81a of the cylinder head cover 81 by the negative pressure introduced from the intake pipe. As a result, the opening 80a may be closed.

[0005] In this case, it becomes difficult for outside air to be introduced into the intake pipe from the opening 80a, and the amount of intake air does not become larger than usual, so that the ISC opening is not adjusted to be abnormally small. Therefore, when the gas recirculation hose 80 is detached from the hose connection portion 83 of the PCV valve 82 and sticks to the cylinder head cover 81, an abnormal state of the blow-by gas recirculation device may not be detected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a gas recirculation hose for recirculating blow-by gas from an engine body to an intake system by connecting a gas recirculation hose to a recirculation gas amount control valve. It is an object of the present invention to provide a connection structure of a recirculation hose in a blow-by gas recirculation device that can more reliably introduce outside air to an intake system via a gas recirculation hose in a state where the recirculation hose is separated from a part.

[0007]

In order to solve the above-mentioned problems, an invention according to claim 1 is provided with a gas recirculation hose for recirculating blow-by gas from a blow-by gas passage of an engine body to an intake system of the engine; A blow-by gas recirculation device comprising a recirculation gas amount control valve for adjusting a flow rate of a recirculated blow-by gas in accordance with a magnitude of a negative pressure introduced from the intake system through a gas recirculation hose; The invention further comprises an opening securing means for securing an opening for introducing outside air into the intake system at the valve-side connection portion when the valve-side connection portion comes off the hose connection portion of the reflux gas amount control valve. And

According to the first aspect of the invention, when the valve side connection of the gas recirculation hose is separated from the hose connection of the recirculation gas amount control valve, the valve side connection end secured by the opening securing means. Outside air is introduced into the intake system from the opening of the air intake system.
For this reason, in the state where the gas recirculation hose is disengaged from the recirculation gas amount control valve, the amount of intake air introduced into the intake system becomes more surely excessive. Therefore, for example, in an operation control device for an engine that performs air-fuel ratio feedback correction for correcting the fuel injection amount based on the oxygen concentration in the exhaust gas, when the gas recirculation hose comes off the recirculation gas amount control valve, the correction value is When the set value is exceeded, it is possible to reliably detect that an abnormality has occurred in the blow-by gas recirculation device.

According to a second aspect of the present invention, in the first aspect of the invention, the opening securing means is configured such that a valve side connection of the gas recirculation hose is disengaged from a hose connection of the recirculation gas control valve, The gist of the present invention is to secure the opening in a state where it is sucked to the engine body by a negative pressure introduced from the intake system.

According to the second aspect of the present invention, the first aspect is provided.
In addition to the operation of the invention described in the above, the valve side connection portion of the gas recirculation hose is disconnected from the hose connection portion of the recirculation gas amount control valve, and when the gas recirculation hose is sucked to the engine body by the negative pressure introduced from the intake system, the opening is Outside air is introduced into the intake system from the opening secured by the securing means. For this reason, the amount of intake air introduced into the intake system becomes excessive when the gas recirculation hose is disengaged from the recirculation gas control valve and is attracted to the engine body.

According to a third aspect of the present invention, in the second aspect of the present invention, the opening securing means is provided at the valve-side connecting portion in a state of being attached to an outer surface of a portion of the engine body. The point is that it is at least one of the part and the valve-side connection part formed in a shape that secures the part.

According to the invention described in claim 3, according to claim 2,
In addition to the effect of the invention described in the above, when the gas recirculation hose is detached from the hose connection portion of the recirculation gas amount control valve and the valve side connection portion is attracted to the outer surface of the set portion of the engine main body, this An opening that opens to the outside is ensured by at least one of the shape of the outer surface of the part and the shape of the valve-side connection part in which the opening is formed. For this reason, it can be implemented without adding a new member to the conventional configuration.

According to a fourth aspect of the present invention, in the first aspect of the invention, the opening securing means is such that the valve side connection of the gas recirculation hose is disconnected from the hose connection of the recirculation gas control valve. The gist of the invention is a hose holding means for holding the posture of the gas recirculation hose so that the valve side connection portion does not stick to the engine body due to a negative pressure introduced from the intake system.

According to the invention described in claim 4, according to claim 1 of the present invention,
In addition to the effect of the invention described in the above, in a state where the valve side connection part of the gas recirculation hose is separated from the hose connection part of the recirculation gas control valve, the posture is held by the hose holding means so as not to be sucked to the engine body. Outside air is introduced into the intake system from the opening of the gas recirculation hose. For this reason, in the state where the gas recirculation hose is disengaged from the recirculation gas control valve, the amount of intake air introduced into the intake system becomes excessive.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, the hose holding means is provided when the valve side connection of the gas recirculation hose is disengaged from the hose connection of the recirculation gas control valve. The gas recirculation hose itself is formed so as to resiliently return to the position and maintain the valve side connection portion at a position away from the engine body.

According to the invention set forth in claim 5, according to claim 4,
In addition to the operation of the invention described in the above, if the valve side connection of the gas recirculation hose is disengaged from the hose connection of the recirculation gas control valve, the gas recirculation hose returns elastically and the valve side connection does not stick to the engine body. Hold in position. Therefore, the present invention is implemented without adding a new member to the conventional configuration.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is embodied in a blow-by gas recirculation device provided in a gasoline engine will be described below with reference to FIGS.

As shown in FIG. 3, the blow-by gas recirculation device 10 includes a cylinder head cover 1 of an engine body 11.
2, a gas recirculation control valve (hereinafter referred to as a PCV valve) 13, a gas recirculation hose 15 for communicating the PCV valve 13 with the intake pipe 14, and a communication between the intake pipe 14 and the inside of the cylinder head cover 12. A fresh air introduction hose 16 is provided.

The gas recirculation hose 15 is made of an elastic material, and one end thereof is connected to the intake pipe 14 on the downstream side of a throttle valve 18 which is opened and closed according to the depression amount of an accelerator pedal (not shown). Further, a valve side connection portion 19 which is the other end of the gas recirculation hose 15 is connected to the PCV valve 13.

As shown in FIG. 1, the PCV valve 13 is mounted in a through hole (not shown) provided on the upper surface 12a of the cylinder head cover 12. In addition, the upper surface 12a is arranged substantially horizontally in a state where the engine body 11 is mounted on the vehicle. The PCV valve 13 includes an upper body portion 13a,
A lower body 13b and a hose connection 13c are provided.
The upper body 13a is located on the upper surface 12 of the cylinder head cover 12.
a, and the lower trunk portion 13b is mounted in a through hole (not shown) provided in the range of the upper surface 12a. The hose connection portion 13c extends upward from the upper surface of the upper body portion 13a. The valve connection portion 19 of the gas recirculation hose 15 is press-fitted to the hose connection portion 13c. PC
The V-valve 13 connects the blow-by gas passage 20 inside the engine main body 11 shown in FIG.

One end of the fresh air introduction hose 16 is connected to the intake pipe 14 on the upstream side of the throttle valve 18, and the other end is connected to a connection portion (not shown) provided on the cylinder head cover 12 to show the inside of the engine body 11. 3 is communicated with a fresh air introduction passage 21 shown in FIG.

In the blow-by gas recirculation device 10 configured as described above, the engine is operated under a light load condition.
When the negative pressure in the intake pipe 14 downstream of the throttle valve 18 is large, the valve opening of the PCV valve 13 increases.
Then, fresh air is introduced into the crankcase from the intake pipe 14 via the fresh air introduction hose 16, and blow-by gas is discharged from the crankcase to the intake pipe 14 via the gas recirculation hose 15. The engine is operated under a high load condition, and the intake pipe 1 downstream of the throttle valve 18 is operated.
When the negative pressure in 4 is small, the valve opening of PCV valve 13 becomes small. Then, the blow-by gas is discharged to the intake pipe 14 via both the fresh air introduction hose 16 and the gas recirculation hose 15.

The gas recirculation hose 15 of this embodiment is characterized by its valve-side connection 19. As shown in FIGS. 1 and 2, the valve-side connection portion 19 of the gas recirculation hose 15 is cut obliquely with respect to its central axis and has a circular opening 19 a. The opening 19a does not open to the outside and communicates with the PCV valve 19 when the valve-side connection 19 is connected to the hose connection 13c of the PCV valve 13.

The gas recirculation hose 15 is connected to the PCV valve 1.
2, the valve-side connection 19 is pulled up by the negative pressure introduced from the intake pipe 14 to the upper surface 1 of the cylinder head cover 12 as shown in FIG.
It sticks to 2a. At this time, the valve-side connection portion 19 sucks in a state substantially perpendicular to the upper surface 12a, so that the opening portion 19a opens to the outside.

According to the above-described embodiment, the following effects can be obtained. (1) As shown in FIG. 2, when the valve-side connection portion 19 of the gas recirculation hose 15 comes off from the hose connection portion 13 c of the PCV valve 13, the upper surface of the cylinder head cover 12 is caused by the negative pressure introduced from the intake pipe 14. It sticks to 12a. At this time, the valve side connection portion 19 sucks in a state substantially perpendicular to the upper surface 12a of the cylinder head cover 12, and
9a is arranged so as to open to the outside. For this reason, the amount of intake air introduced into the intake pipe 14 becomes excessive when the gas recirculation hose 15 comes off the PCV valve 13 and comes off.

Therefore, in the engine operation control device for performing the air-fuel ratio feedback correction based on the oxygen concentration in the exhaust gas, when the gas recirculation hose 15 is disengaged from the PCV valve 13, the air-fuel ratio feedback correction coefficient is set to a predetermined value. It is possible to reliably detect that an abnormality has occurred in the blow-by gas recirculation device 10 by exceeding it.

(2) When the valve side connection portion 19 of the gas recirculation hose 15 comes off from the hose connection portion 13c, the gas recirculation hose 15 resiliently returns to a predetermined posture and the valve side connection portion 19 cut obliquely. The opening 19a of the valve-side connection portion 19 that is attached to the cylinder head cover 12 is disposed so as to open to the outside. For this reason, the present invention can be implemented without adding a new member to the conventional configuration, and the number of parts and the number of assembling steps are not increased. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. Note that the present embodiment is different from the first embodiment only in that the valve-side connection portion 19 of the gas recirculation hose 15 of the first embodiment is changed to a valve-side connection portion 30. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted, and only the valve-side connecting portion 30 will be described in detail.

As shown in FIG. 4, the valve-side connecting portion 30 is cut so as to be orthogonal to its central axis, and has a circular opening 30.
a. Also, the valve side connection part 30 has an opening 3
At one point on the periphery of Oa, a rectangular cutout portion 31 opening on the peripheral surface is formed. Notch 31
Is formed so as not to open to the outside when connected to the hose connection portion 13c of the PCV valve 13, as shown by a two-dot chain line in FIG.

The gas recirculation hose 15 is connected to the PCV valve 1.
When the hose 3 comes off from the hose connection portion 13c, the opening 30a of the valve side connection portion 30 sticks to the upper surface 12a of the cylinder head cover 12 due to the negative pressure introduced from the intake pipe 14. At this time, the valve side connection portion 30 is sucked substantially perpendicularly to the upper surface 12a, and communicates with the outside via the cutout portion 31.

According to the present embodiment described in detail above, in addition to the effects described in (1) and (2) of the first embodiment,
The following effects can be obtained. (1) In the case of the first embodiment, the gas recirculation hose 15
If the elastic coefficient of the PCV valve 13 is small or the length thereof is long, the valve-side connection portion 19 sucks in a state perpendicular to the upper surface 12a of the cylinder head cover 12 when the PCV valve 13 comes off from the hose connection portion 13c and comes off. Without opening 19
It is conceivable that a is closed. In the case of the present embodiment, at least one of the opening 30a and the notch 31 is reliably opened to the outside even if the valve-side connection portion 30 does not stick vertically to the upper surface 12a. For this reason, the amount of intake air introduced into the intake pipe 14 becomes more reliably excessive, and it is possible to more reliably detect that an abnormality has occurred. (Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. This embodiment differs from the first embodiment only in that the cylinder head cover 12 is changed to the cylinder head cover 40 and the gas recirculation hose 15 is the same gas recirculation hose 42 as the conventional gas recirculation hose 80. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Only the cylinder head cover 40 and the gas recirculation hose 42 will be described in detail.

As shown in FIG. 6, an end portion 41 as a portion of the cylinder head cover 40 has an outer side surface 41a which is inclined with respect to a horizontal plane when the engine body 11 is mounted on a vehicle. The end 41 is provided with a convex portion 41b for fixing the PCV valve 13. The upper surface of the convex portion 41b is formed to be substantially horizontal, and the PCV valve 13 is mounted in a through hole (not shown) provided in the upper surface.

The gas recirculation hose 42 has a valve-side connection portion 43 connected to the hose connection portion 13c of the PCV valve 13. As shown in FIG. 6, the valve-side connection portion 43 is cut so as to be orthogonal to the central axis and has a circular opening 43a, similarly to the conventional gas recirculation hose 80.

When the valve-side connecting portion 43 comes off from the hose connecting portion 13c of the PCV valve 13 and comes off, as shown in FIG. 6, the gas recirculation hose 42 is turned off by the negative pressure introduced from the intake pipe 14. At the valve-side connection portion 43, it sticks to the outer surface 41a of the end portion 41. At this time, the valve-side connecting portion 43 sucks on the outer side surface 41a in a substantially vertical posture, so that the opening 43
a is opened to the outside.

According to the above-described embodiment, the following effects can be obtained. (1) As shown in FIG. 6, when the valve side connection portion 43 of the gas recirculation hose 42 comes off from the hose connection portion 13 c of the PCV valve 13, the outside of the cylinder head cover 40 is removed by the negative pressure introduced from the intake pipe 14. It sticks to the side surface 41a.
At this time, the valve-side connecting portion 43 sucks in a state substantially perpendicular to the outer surface 41a of the end portion 41, and the inclined outer surface 41a
The opening 43a of the valve-side connection portion 43 that abuts on is opened to the outside. Therefore, the gas recirculation hose 42 is connected to the PCV valve 13
In the state where the intake air is removed from the intake pipe 14, the intake air amount introduced into the intake pipe 14 becomes excessive.

(2) The valve connecting portion 43 is the hose connecting portion 1
Since the opening 43a is opened to the outside by the inclined outer surface 41a which sticks when it comes off from the position 3c, it is only necessary to mount the PCV valve 13 on the end 41 of the cylinder head cover 40 having the inclined outer surface 41a. it can. (Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. This embodiment is different from the first embodiment only in that the cylinder head cover 12 of the first embodiment is changed to a cylinder head cover 50 and the gas recirculation hose 15 is changed to a gas recirculation hose 51. Accordingly, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Only the cylinder head cover 50 and the gas recirculation hose 51 will be described in detail.

As shown in FIG. 7, the end portion 52 of the cylinder head cover 50 has an outer side surface 52a which is disposed substantially vertically when the engine body 11 is mounted on a vehicle. A through hole (not shown) is provided in the end portion 52, and the PCV valve 13 is fixed to the through hole. PCV valve 13
Is mounted such that the hose connection portion 13c extends substantially in the horizontal direction.

One end of the gas recirculation hose 51 is connected to the intake pipe 14 from above, and the other end of the valve side connection 53
It is connected to the hose connection part 13c of the CV valve 13. The gas recirculation hose 51 is formed to be a straight pipe in a natural state, and is connected to the intake pipe 14 and the PCV valve 13 in a state of being bent into an “L” shape by elastic deformation. As shown in FIG. 7, the gas reflux hose 51 has a
When the CV valve 13 comes off from the hose connection portion 13c, it is elastically restored to a straight tubular shape. Then, the valve side connection portion 53 is held at a position away from the outer side surface 52a of the end portion 52, and the opening 53a of the valve side connection portion 53 is sucked to the cylinder head cover 50 by the negative pressure introduced from the intake pipe 14. Not to be. In this state, the gas recirculation hose 51 is connected to the opening 53 so that outside air is introduced into the intake pipe 14.
a is held at a position that opens to the outside.

According to the above-described embodiment, the following effects can be obtained. (1) As shown by a two-dot chain line in FIG. 7, when the gas recirculation hose 51 comes off from the hose connection portion 13c of the PCV valve 13, the gas recirculation hose 51 elastically returns until it becomes a substantially straight tube and the valve side Connect the connecting part 53 to the cylinder head cover 50
Hold it in a position where it does not stick to. For this reason, the opening 53a of the valve side connection part 53 is opened to the outside, and this opening 53
Outside air is introduced into the intake pipe 14 from a. As a result, the amount of intake air introduced into the intake pipe 14 when the gas recirculation hose 51 is disengaged from the PCV valve 13 becomes excessive. Therefore, the first
The effect described in (1) of the embodiment can be obtained.

(2) When the valve side connecting portion 53 comes off the hose connecting portion 13c of the PCV valve 13, the gas recirculation hose 51
Resiliently holds the valve side connection portion 53 at a position where it does not stick to the cylinder head cover 50. For this reason, it can be implemented without adding a new member to the conventional configuration.

Hereinafter, embodiments other than the above embodiment will be described in a bulleted form. In the second embodiment, the shape of the notch is not limited to a substantially square shape, but may be, for example, a substantially semicircular shape or a substantially triangular shape.

In the second embodiment, the number of cutouts may be plural. In the fourth embodiment, when the gas recirculation hose 51 is disconnected from the hose connection portion 13c of the PCV valve 13 and comes off the hose holding means, the gas recirculation hose 51 is moved so that the valve side connection portion 53 is moved to the cylinder head cover. It is a coil spring that is held at a position where it does not stick to 50. The coil spring is mounted so as to fit over the gas recirculation hose 51, and elastically returns to a cylindrical shape in a natural state. Also in this case, the amount of intake air introduced into the intake pipe 14 can be made excessive with the gas recirculation hose 51 disconnected from the PCV valve 13.

In the first, second and third embodiments,
When the gas recirculation hose comes off the hose connection of the recirculation gas amount control valve, the object to which the valve-side connection sticks is not limited to the engine body, but may be an intake manifold, an intake pipe cover, a surge tank, or the like. Further, it may be a panel constituting a vehicle body.

In each of the above embodiments, the recirculated gas amount control valve is not limited to the PCV valve 13 fixed to the cylinder head cover, but a hose connected to the cylinder head cover so as to communicate with the blow-by gas passage 20 and a gas recirculation valve. It may be provided so as to connect with a hose.
In this case, when the gas recirculation hose is disengaged from the recirculation gas amount control valve, the amount of intake air introduced into the intake system can be more reliably increased, and an abnormal state can be more reliably detected. I do.

Hereinafter, the technical ideas grasped from each of the above embodiments will be described together with their effects. (1) The invention according to any one of claims 1 to 5, wherein the recirculation gas amount control valve is fixed to the engine body. Connection structure.

(2) In the invention according to claim 4,
The hose holding means elastically returns when the valve side connection of the gas recirculation hose comes off the hose connection of the recirculation gas amount control valve, and holds the valve side connection at a position away from the engine body. A connection structure of a gas recirculation hose in a blow-by gas recirculation device, wherein the connection member is a spring member. Even with such a configuration, outside air can be introduced into the intake system in a state where the gas recirculation hose is separated from the recirculation gas amount control valve.

(3) In the second aspect of the present invention,
The opening securing means is configured to attach the opening to the valve-side connecting portion in a state where the opening is secured to an outer surface of the vehicle auxiliary device (an intake manifold, an intake pipe cover, a surge tank) or a portion (panel) of a vehicle body component. A connection structure of a gas recirculation hose in a blow-by gas recirculation device, wherein the connection structure is at least one of a portion formed in a shape to be secured and a valve-side connection portion. Such a configuration can also be implemented without adding new members to the conventional configuration.

(4) In the invention according to claim 2,
The blow-by opening means is a valve-side connection portion formed in a shape to secure the opening portion at the valve-side connection portion in a state of being attached to an outer surface of a portion of the engine body. Connection structure of gas recirculation hose in gas recirculation device. According to such a configuration, in the conventional gas recirculation hose, it can be implemented only by changing the form of the valve-side connection portion forming the opening.

(5) In the invention described in the above (4), the valve-side connection portion is formed by being cut obliquely with respect to a center axis thereof. According to such a configuration, it can be implemented only by cutting the conventional gas recirculation hose diagonally, and the number of processing steps does not increase.

(6) In the invention described in the above (4), the valve-side connecting portion is cut so as to be orthogonal to its central axis, and has an opening at the periphery of the opening. It is characterized in that at least one notch is formed. According to such a configuration,
Even when the valve-side connection portion does not stick vertically to the outer surface of the engine body, the outside air can be reliably introduced into the intake system.

(7) A blow-by gas recirculation device having a connection structure of a recirculation hose in the blow-by gas recirculation device according to any one of claims 1 to 5, and the blow-by gas based on a detected air-fuel ratio. An engine system comprising: an abnormality diagnosis device that diagnoses an abnormality of the recirculation device. According to such a configuration, it is possible to reliably detect that the gas recirculation hose is disconnected from the connection portion with the PCV valve.

[0051]

According to the present invention, the gas recirculation hose for recirculating blow-by gas from the engine body to the intake system is disconnected from the connection with the recirculation gas amount control valve. Thus, outside air can be more reliably introduced into the intake system via the gas recirculation hose.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a connection structure of a gas recirculation hose of a first embodiment.

FIG. 2 is a schematic view showing an operation state of a gas recirculation hose.

FIG. 3 is a schematic diagram showing a blow-by gas recirculation device.

FIG. 4 is a schematic perspective view showing a connection structure of a gas reflux hose according to a second embodiment.

FIG. 5 is a schematic view showing an operation state of a gas recirculation hose.

FIG. 6 is a schematic view showing an operation state of a cylinder head cover and a gas recirculation hose of a third embodiment.

FIG. 7 is a schematic diagram showing an operation state of a gas recirculation hose of a fourth embodiment.

FIG. 8 is a schematic perspective view showing a conventional gas reflux hose connection structure.

FIG. 9 is a schematic view showing an operation state of the gas recirculation hose.

[Explanation of symbols]

10: blow-by gas recirculation device, 11: engine body,
12 ... Cylinder head cover as engine body, 1
3 ... Reflux gas amount control valve, 13c ... Hose connection part, 14 ...
Intake pipe as intake system, 15 gas recirculation hose, 19 ...
Valve-side connecting portion as opening securing means, 19a ... opening,
Reference numeral 20: blow-by gas passage, 30: valve-side connection part as opening securing means, 30a: opening, 31 ... notch as opening, 40: cylinder head cover as opening securing means and engine body, 41 ... End portion as a part, 41a outside surface, 42 gas recirculation hose, 43 valve side connection portion, 43a opening portion, 50 cylinder head cover as engine body, 51 opening portion securing means and hose holding means Gas recirculation hose 53, valve side connection, 53a opening.

Claims (5)

[Claims] 1. A gas recirculation hose for recirculating blow-by gas from a blow-by gas passage of an engine body to an intake system of an engine, and according to a magnitude of a negative pressure introduced from the intake system via the gas recirculation hose. A recirculation gas amount control valve for adjusting the flow rate of the blow-by gas to be recirculated. When the valve-side connection portion of the gas recirculation hose is disconnected from the hose connection portion of the recirculation gas amount control valve, A connection structure of a gas recirculation hose in a blow-by gas recirculation device, comprising an opening securing means for securing an opening for introducing outside air into the intake system at the valve-side connection portion. 2. The opening securing means according to claim 1, wherein a valve side connection of said gas recirculation hose is disengaged from a hose connection of said recirculation gas control valve, and is attracted to said engine body by a negative pressure introduced from said intake system. The connection structure for a gas recirculation hose in the blow-by gas recirculation device according to claim 1, wherein the opening is secured in a state where the gas recirculation hose is opened. 3. The portion and the valve-side connection portion formed in a shape that secures the opening at the valve-side connection portion in a state where the opening portion is secured to an outer surface of a portion of the engine body. The connection structure of a gas recirculation hose in the blow-by gas recirculation device according to claim 2, wherein the gas recirculation hose is at least one of: 4. The valve securing means according to claim 1, wherein said valve side connection portion of said gas recirculation hose is disconnected from a hose connection portion of said recirculation gas control valve by a negative pressure introduced from said intake system. The connection structure for a gas recirculation hose in a blow-by gas recirculation device according to claim 1, wherein the connection portion is a hose holding means for holding the posture of the gas recirculation hose so as not to be attracted to the engine body. 5. The hose holding means resiliently returns when the valve connection of the gas recirculation hose is disengaged from the hose connection of the recirculation gas control valve, and separates the valve connection from the engine body. The connection structure of the gas recirculation hose in the blow-by gas recirculation device according to claim 4, wherein the gas recirculation hose itself is formed so as to be held at the position.