JP6493060B2 - PCV valve - Google Patents

Description

  The present invention relates to a PCV valve provided in a blow-by gas passage that connects a crank chamber of an internal combustion engine and an intake pipe.

  In an internal combustion engine such as a vehicle, unburned air-fuel mixture and blow-by gas that is combustion gas leak from a combustion chamber above the piston. The blow-by gas mixes with the oil mist flying around due to the lubrication of the internal combustion engine, thereby deteriorating the oil and lowering the function of the internal combustion engine. Therefore, blow-by gas is introduced into the intake pipe, returned to the crank chamber, and recombusted. Here, a PCV valve is provided in the blow-by gas passage between the crank chamber and the intake pipe in order to adjust the intake amount of blow-by gas in accordance with the load of the operating state of the internal combustion engine and control the amount of fresh air introduced. In this regard, for example, Patent Document 1 discloses an apparatus for controlling the blow-by gas flow rate to an appropriate value.

Japanese Utility Model Publication No. 62-141610

  By the way, since oil mist is contained in blow-by gas, an oil mist separator is attached to the crank block and the cylinder head to separate and remove the oil mist inside. However, the oil mist separator does not completely remove the oil mist but slightly remains in the blow-by gas and flows as it is with the blow-by gas. During the operation of the internal combustion engine, the oil mist remaining inside the blow-by gas flowing through the PCV valve comes into contact with the regulating valve body and the like in the PCV valve and is collected therein. In particular, the oil mist is easily collected because the flow path is restricted in the portion where the regulating valve body is provided inside the PCV valve.

  Here, in order to prevent the blow-by gas from flowing backward from the intake pipe side to the crank chamber side when the internal combustion engine is stopped or backfired, the conventional PCV valve is described in Patent Document 1 and the like. When the internal combustion engine is stopped, the inflow side end of the adjusting valve body disposed in the valve body is brought into contact with the inlet side of the valve body by the urging force of the spring in the valve body to close the inlet. It has a structure.

  For this reason, the oil adhering to the inner wall of the regulating valve body and the valve body is discharged from the outlet of the valve body to the intake pipe side because the inlet is closed when the internal combustion engine is stopped. As described above, when the oil in the valve body is discharged to the intake pipe side, the amount of oil consumed for recombustion increases and also causes a deposit (sediment) in the intake pipe.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a PCV valve that can prevent oil in the valve body from flowing out to the intake pipe side when the internal combustion engine is stopped.

In order to solve the above problem, the invention according to claim 1 is provided in a blow-by gas passage that communicates a crank chamber and an intake pipe of an internal combustion engine, and controls a flow rate of blow-by gas according to an operating state of the internal combustion engine. A PCV valve to be adjusted, in which a flow path for the blow-by gas is formed, a tubular valve body having an inlet and an outlet for the blow-by gas, and a reciprocatingly movable inside the valve body A regulating valve body, and a spring for biasing the inflow side end of the regulation valve body toward the inlet side of the valve body. closable flange is provided a flow path for the blow-by gas in contact with the protrusion provided on the inner wall, said valve body is provided in the blow-by gas passage so that its axial direction is horizontal To the valve body, the and drain hole is provided for the oil in the valve body when the stop of the internal combustion engine back to the crank chamber, wherein the drain hole is stepped or on the bottom of the inner peripheral wall of the valve body The gist is to provide a groove-shaped discharge passage formed by providing an inclination .
According to a second aspect of the present invention, in the first aspect of the present invention, the drain hole is provided at an end portion on the inflow side in the axial direction of the valve body and is spaced downward from the inlet of the blow-by gas. The gist is that it is provided .
According to a third aspect of the present invention, in the first or second aspect of the present invention, an annular bead that protrudes toward the other abutment surface is provided on one abutment surface of the convex portion and the flange. The gist is that is provided.
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the valve body can be attached to a passage forming portion that forms the blow-by gas passage via an attachment. The gist of the invention is that positioning means is provided between the valve body and the passage forming portion so as to position the drain hole at the lowermost portion of the valve body.
The invention according to claim 5 is the invention according to any one of claims 1 to 3, wherein the valve main body can be attached to a passage forming portion that forms the blow-by gas passage via an attachment. The gist of the invention is that a plurality of drain holes are provided at equal intervals of a predetermined angle along a circumferential direction centered on the axis of the valve body.
The invention according to claim 6 is the invention according to any one of claims 1 to 3, wherein the valve body is provided integrally with a passage forming portion that forms the blow-by gas passage. And

According to the PCV valve of the present invention, a flange capable of closing the flow passage of the blow-by gas by contacting a convex portion provided on the inner wall of the valve body is provided at the front end of the intake side of the regulating valve body. Is provided with a drain hole for returning the oil in the valve body to the crank chamber when the internal combustion engine is stopped. Thereby, when the internal combustion engine is stopped or backfired, the blow-by gas flows backward from the intake pipe side to the crank chamber side by closing the flow path of the blow-by gas by the flange on the intake side tip of the regulating valve body. Can be prevented. In particular, when the internal combustion engine is stopped, the oil in the valve body is discharged from the drain hole due to its own weight and returned to the crank chamber. As a result, an increase in oil consumption can be suppressed, and the occurrence of deposits in the intake pipe can be suppressed.
Further, when the drain hole is provided at the inflow side end of the valve main body in the axial direction, the oil in the valve main body can be more reliably returned to the crank chamber.
Further, when an annular bead that protrudes toward the other abutment surface is provided on one abutment surface of the projection and the flange, the blowby gas is brought into contact with the abutment between the projection and the flange. Is more reliably closed.
Further, when the valve main body can be attached to a passage forming portion that forms the blow-by gas passage via an attachment portion, and a positioning means is provided between the valve main body and the passage forming portion, When the PCV valve is in use, the drain hole is positioned at the lowermost part of the valve body by positioning the valve body by the positioning means. Therefore, the oil in the valve body can be returned to the crank chamber more reliably.
In addition, the valve body can be attached to a passage forming portion that forms the blow-by gas passage via an attachment portion, and the drain hole is predetermined along a circumferential direction centering on an axis of the valve body. When a plurality of drain holes are provided at equal intervals, any drain hole of the plurality of drain holes is positioned at the lowermost part of the valve body or in the vicinity thereof when the PCV valve is in use. Therefore, the oil in the valve body can be returned to the crank chamber more reliably.
Further, when the valve main body is provided integrally with a passage forming portion that forms the blow-by gas passage, the drain hole is positioned at the lowermost portion of the valve main body when the PCV valve is in use. Therefore, the oil in the valve body can be returned to the crank chamber more reliably.

The present invention will be further described in the following detailed description with reference to the drawings referred to, with reference to non-limiting examples of exemplary embodiments according to the present invention. Similar parts are shown throughout the several figures.
It is sectional drawing which shows the PCV valve | bulb of 1st embodiment of this invention. It is a left view of the valve body of FIG. It is a right view of the valve body of FIG. It is an expanded sectional view of the flange and convex part of FIG. It is an expanded sectional view which shows the modification of the flange and convex part of FIG. It is an expanded sectional view which shows the fixing method of the flange of FIG. It is an expanded sectional view which shows another fixing method of the flange of FIG. It is sectional drawing which shows the position of the adjustment valve body at the time of light load of an internal combustion engine. It is sectional drawing which shows the position of the adjustment valve body at the time of high load of an internal combustion engine. It is sectional drawing which shows the position of the adjustment valve body at the time of a stop of an internal combustion engine. It is sectional drawing which shows the modification of the PCV valve | bulb of FIG. It is a left view which shows the modification of the valve main body of FIG. It is sectional drawing which shows the PCV valve | bulb of 2nd embodiment of this invention. The valve main body of FIG. 13 is shown, (a) is a left view, (b) is a principal part front view. It is a right view of the valve body of FIG. It is a principal part front view which shows the modification of the drain hole of FIG. It is a left view which shows another modification of the drain hole of FIG. It is sectional drawing which shows the PCV valve | bulb of 3rd embodiment of this invention. It is sectional drawing which shows the modification of the PCV valve | bulb of FIG.

  The items shown here are exemplary and illustrative of the embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

<PCV valve>
The PCV valve according to the present embodiment is a PCV valve (1) that is provided in a blow-by gas passage that connects a crank chamber of an internal combustion engine and an intake pipe, and adjusts the flow rate of the blow-by gas in accordance with the operating state of the internal combustion engine. (For example, see FIG. 1, FIG. 11, FIG. 13, FIG. 18 and FIG. 19). A flow passage (11a) for blow-by gas is formed inside, a tubular valve body (11) having a blow-by gas inlet (12) and an outlet (13), and reciprocating inside the valve body. And a spring (51) for urging the inflow side end of the adjustment valve body toward the inlet of the valve body. In addition, the intake-side tip (43) of the regulating valve body (41) is in contact with a convex portion (27) provided on the inner wall (14) of the valve body (11), so that the blow-by gas flow path (11a) ) Is provided. Further, the valve body (11) is provided with a drain hole (30) for returning the oil (O) in the valve body to the crank chamber when the internal combustion engine is stopped.

  As the PCV valve according to the present embodiment, for example, the drain hole (30) is provided at the axial inflow end of the valve body (11) (for example, FIG. 1, FIG. 11, FIG. 13). , And FIG. 18 and the like).

  As the PCV valve according to the present embodiment, for example, one of the convex portions (27) and the flange (44) is provided with an annular bead (27a, 44a) (for example, see FIGS. 4 and 5). In this case, it is preferable that a bead (44a) is provided on the flange (44) from the viewpoint of improving the accuracy of the contact surface of the convex portion.

  As the PCV valve according to the present embodiment, for example, the spring (51) is interposed between the inflow side end (42) and the convex portion (27) of the regulating valve body (41) ( For example, see FIG. Thereby, a valve body can be made into a simple structure.

  As the PCV valve according to the present embodiment, for example, the valve main body (11) can be attached to a passage forming portion (61) that forms a blow-by gas passage via a fitting (63). Positioning means (18a, 61a) for positioning the drain hole (30) so as to be positioned at the lowermost part of the valve body is provided between the forming portion (see, for example, FIGS. 1 and 3). Can be mentioned.

  As the PCV valve according to the present embodiment, for example, the valve main body (11) can be attached to a passage forming portion (61) that forms a blow-by gas passage via a fitting (63), and a drain hole (30 ) May include a B form (see, for example, FIG. 13 and FIG. 14) that is provided in a plurality at equal intervals along the circumferential direction around the axis of the valve body.

  As the PCV valve according to the present embodiment, for example, the valve main body (11) is a C form (for example, FIGS. 18 and 19) provided integrally with a passage forming portion (61) that forms a blow-by gas passage. Reference).

  In the A to C forms, for example, the passage forming portion may be an oil mist separator (61) for capturing oil mist contained in blow-by gas (for example, FIG. 1, FIG. 11, FIG. 13). FIG. 18 and FIG. 19 etc.). Further, in the above A and C forms, for example, the drain hole (30) can be provided with a groove-shaped discharge passage (33) formed in the inner wall (14) of the valve body (11) (for example, FIG. 1, FIG. 11, FIG. 18 and FIG. 19 etc.). In this case, it is preferable that the bottom surface of the discharge passage (33) is inclined with respect to the axial direction of the valve body (11) from the viewpoint of oil dischargeability (see, for example, FIGS. 11 and 19). .

<PCV valve mounting structure>
The PCV valve mounting structure according to the present embodiment is, for example, a PCV valve mounting structure in which the PCV valve (1) of the above embodiment is provided in the blow-by gas passage, and the drain hole (30) 11) or the vicinity thereof (see, for example, FIG. 1, FIG. 11, FIG. 13, FIG. 18 and FIG. 19).

  In addition, the code | symbol in the parenthesis of each structure described in the said embodiment shows the correspondence with the specific structure as described in the Example mentioned later.

<First embodiment>
Hereinafter, a PCV valve according to a first embodiment of the present invention will be described with reference to the drawings.

  The PCV (Positive Crankcase Ventiration) valve is provided in the blow-by gas passage that connects the crank chamber of the internal combustion engine and the intake pipe, and adjusts the flow rate of the blow-by gas in the blow-by gas passage according to the operating state of the internal combustion engine. Yes, the PCV valve of this embodiment is installed sideways in the internal combustion engine. As shown in FIG. 1, the PCV valve 1 includes a tubular valve body 11 having a blow-by gas flow passage 11 a formed therein and having an inlet 12 and an outlet 13 for blow-by gas B; An adjustment valve body 41 that is reciprocally movable and a spring 51 that urges the inflow side end portion 42 of the adjustment valve body 41 toward the inlet 12 of the valve body 11 are provided. Further, the adjustment valve body 41 is provided with a flange 44 that can close the blow-by gas passage 11 a at the intake-side distal end portion 43. The valve body 11 is provided with a drain hole 30 in the lowermost portion 29 of the inner wall 14 for returning the oil in the valve body 11 to the crank chamber when the internal combustion engine is stopped. Hereinafter, each component will be described in detail.

  First, the valve body 11 projects laterally, that is, horizontally, with respect to a cylinder head cover 61 (illustrated as a “passage forming portion” according to the present invention) that forms a blow-by gas passage, via a fixture 63 described later. It is attached in the state. This cylinder head cover 61 constitutes a housing of a known oil mist separator (not shown) for capturing oil mist contained in blow-by gas. Therefore, the valve body 11 is disposed on the downstream side of the oil mist separator.

  The valve body 11 is formed of a metal material or a resin material, and as shown in FIG. 1, the valve body 11 is formed in a substantially circular tube shape as a whole, and the hollow portion extending in the tube axis direction forms a blow-by gas channel 11a. A regulating valve element 41 is accommodated in the blow-by gas passage 11a. In FIG. 1, the left end portion of the valve body 11 is an inflow side end portion 15 into which the blow-by gas B from the crank chamber flows, and the right end portion flows out of the blow-by gas B through the intake pipe side. It becomes the outflow side edge part 16 which does. As shown in FIG. 2, the inflow side end portion 15 is closed by a disc-like lid portion 17, and an inflow port 12 into which blow-by gas B flows is formed at the center of the inflow side end portion 15. .

  A flange 18 that protrudes in a direction perpendicular to the tube axis is formed at the longitudinal center of the valve body 11. The flange portion 18 is formed in a substantially annular shape and is formed in a shape in which only the upper end portion protrudes, and this protruding portion constitutes a positioning portion 18a. In production, the valve body 11 is divided into a left inflow side half 21 and a right outflow side half 22 at the flange 18 part, which are bonded, welded, fitted, screwed, or the like. It is assembled together. The inflow side half portion 21 is formed by the cylindrical portion 23 and the inflow side flange portion 19, and an adjustment valve body 41 is accommodated therein so as to be able to reciprocate in the tube axis direction, and the outer wall portion of the end portion on the inflow side A locking portion 24 that bulges outward is formed in an annular shape, and a tip end portion of a grommet 63 described later is locked to the locking portion 24 so that the inflow side half portion 21 of the valve body 11 is prevented from coming off. Yes.

  The outflow side half 22 is formed by the cylindrical portion 25 and the outflow side flange 20, and an intake pipe is connected to the outflow side of the small diameter cylindrical portion 25. A retaining protrusion 26 is formed on the outer wall portion at the tip of the cylindrical portion 25 to prevent the intake pipe from being pulled out. Further, on the side of the outflow side half 22 that faces the inflow side half 21, an annular convex portion 27 is provided in a direction perpendicular to the tube axis from the inner wall 14.

  Further, the valve body 11 has a drain hole 30 extending over the lower end portion of the lid portion 17 and the inflow side peripheral portion of the bottom portion 28 of the inner wall 14. In the drain hole 30, a circular through hole 31 is formed at the lower end portion of the lid portion 17, and a step 32 is provided in the peripheral portion on the inflow side of the bottom portion 28 of the inner wall 14. A communicating groove-shaped discharge passage 33 is formed, and the oil O staying in the bottom portion 28 is discharged from the drain hole 30 to the crank chamber side through the discharge passage 33 as described later. An inflow side peripheral portion of the bottom portion 28 of the inner wall 14 is a lowermost portion 29 of the inner wall 14 of the valve body 11. The through hole 31 may have a circular shape, an elliptical shape, or the like in addition to a circular shape.

  Next, the adjustment valve body 41 accommodated in the valve body 11 is formed of a metal material or a resin material, and includes a large diameter cylindrical portion 45, a small diameter cylindrical portion 46, and a truncated cone portion 47 located in the middle thereof. The flange 42a is formed in an annular shape at the inflow side end portion 42 of the large-diameter cylindrical portion 45. The truncated cone portion 47 linearly decreases in diameter from the large-diameter column portion 45 toward the small-diameter column portion 46, and the outer peripheral surface is a tapered surface. The truncated cone portion 47 adjusts the flow rate of the blow-by gas B flowing through this portion in association with the convex portion 27 of the valve body 11. A disc-shaped flange 44 that protrudes in a direction perpendicular to the tube axis is provided at the suction-side tip portion 43 that is the tip portion on the outflow side of the small-diameter cylindrical portion 46.

  As shown in FIG. 4, the flange 44 has an annular bead 44 a protruding in an annular shape at the peripheral end of the facing surface (that is, the contact surface) facing the convex portion 27 of the valve body 11. The tip of the bead 44a comes into contact with the opposing surface (that is, the contact surface) of the convex portion 27 of the valve body 11 to seal this portion. When the flange 44 and the convex portion 27 of the valve body 11 are in contact with each other, since the sealing is incomplete, the bead 44a is provided to improve the sealing performance. The cross-sectional shape of the bead 44a may be formed in a quadrilateral shape, a trapezoidal shape, an elliptical shape, a semicircular shape, or the like other than the triangular shape.

  Regarding the sealing performance between the flange 44 and the convex portion 27 of the valve body 11, as shown in FIG. 5, a bead 27 a having a quadrangular cross section is annularly formed on the facing surface of the convex portion 27 of the valve body 11 facing the flange 44. It is good also as what protrudes in this and makes the part of this bead 27a contact | abut on the opposing surface of the flange 44. FIG. In this case as well, the bead 27a may be formed in a trapezoidal shape, an elliptical shape, a semicircular shape, or the like in addition to a square cross section.

  Further, when the flange 44 is formed of a metal material and the adjustment valve body 41 is also formed of a metal material, as shown in FIG. 6, the fixing hole 44b provided in the center is in the intake side of the adjustment valve body 41. The fixing valve body 41 can be fixed to the adjusting valve body 41 by press-fitting a fixed shaft 48 that protrudes integrally in the axial direction from the end face of the tip portion 43. When both the flange 44 and the adjustment valve body 41 are formed of a resin material, as shown in FIG. 7, the intake-side tip portion 43 of the adjustment valve body 41 is inserted into a fixing hole 44 b provided at the center of the flange 44. It is possible to fix to the adjustment valve body 41 by inserting a fixed shaft 48 projecting in the axial direction from the outside and caulking from the outside. With these fixings, the flange 44 can be easily and stably fixed to the intake side distal end portion 43 of the adjustment valve body 41.

  The flange 44 formed and fixed in this manner is provided between the convex portion 27 and the outflow side end portion 16 of the valve body 11 as the adjusting valve body 41 moves in the blow-by gas flow path 11a of the valve body 11. Is moved in the tube axis direction and comes into contact with the convex portion 27 of the valve body 11, the blow-by gas flow path 11 a is blocked, and the internal space of the valve body 11 is divided into two with the flange 44 as a boundary.

  Next, a coiled spring 51 is fitted on the outer peripheral side of the adjustment valve body 41 inside the cylindrical portion 23 of the valve body 11. The spring 51 is interposed between the convex portion 27 of the valve body 11 and the flange portion 18 of the adjustment valve body 41, and constantly urges the adjustment valve body 41 toward the lid portion 17 of the valve body 11. In this sense, the convex portion 27 of the valve body 11 also serves as a valve seat for the spring 51.

  In the present embodiment, the valve body 11 is fixed to the cylinder head cover 61 using a resin or rubber grommet 63 as an attachment. As shown in FIG. 3, the grommet 63 has a substantially annular shape on the side of the intake pipe, and only the upper end portion is formed in a shape protruding outward in a U shape, and has a keyhole shape as a whole. As described above, the flange portion 18 at the intermediate portion of the valve body 11 is formed with the positioning portion 18a protruding at the upper end portion, and the shape of the grommet 63 corresponds to this. The flange portion 18 is accommodated inside the portion of the grommet 63 on the intake pipe side.

  On the other hand, as shown in FIG. 3, a pair of arc-shaped positioning ribs 61 a project from the left and right sides of the U-shaped portion of the upper end of the grommet 63 at the fixed position of the PCV valve 1 in the cylinder head cover 61. . The pair of left and right positioning ribs 61 a are slightly spaced outward from the U-shaped forming part of the grommet 63. Thereby, the PCV valve 1 is fixed to the cylinder head cover 61 at a fixed position in the circumferential direction, that is, at a position where the U-shaped formation portion of the flange portion 18 of the valve body 11 is directly above. The positioning portion 18a of the valve body 11 and the U-shaped portion of the grommet 63 and the pair of left and right positioning ribs 61a of the cylinder head cover 61 constitute the “positioning means” of the present invention.

Next, the operation of the thus configured PCV valve 1 of the present embodiment will be described.
First, when the internal combustion engine is operated and the vehicle is in a light load state such as idling or deceleration, the negative pressure in the intake pipe is large as shown in FIG. Therefore, the spring 51 is greatly compressed, and the adjustment valve body 41 moves greatly toward the intake pipe against the urging force of the spring 51. At this time, since the large-diameter portion of the truncated cone portion 47 of the adjustment valve body 41 is positioned at the peripheral corner portion 27b on the inflow side of the convex portion 27 of the valve body 11, the peripheral corner portion of the convex portion 27 of the valve body 11 The gap between 27b and the truncated cone part 47 is quite small. For this reason, the intake amount of the blow-by gas B to the intake pipe side is considerably suppressed, and the amount of fresh air introduced is correspondingly controlled accordingly. The blow-by gas B flowing to the intake pipe side is introduced into the combustion chamber and recombusted.

  On the other hand, when the internal combustion engine is operated and the vehicle is in a high load state such as when the vehicle is accelerated, the negative pressure in the intake pipe is small as shown in FIG. 9, and the tensile force due to intake air from the intake pipe side is the biasing force of the spring 51. Although it is larger, it is smaller than the light load state. For this reason, the compression amount of the spring 51 is small and the adjustment valve element 41 moves to the intake pipe side against the urging force of the spring 51, but the movement amount is smaller than that in the light load state. At this time, since the small-diameter portion of the truncated cone portion 47 of the adjustment valve body 41 is located at the peripheral corner portion 27b on the inflow side of the convex portion 27 of the valve body 11, the peripheral corner portion of the convex portion 27 of the valve body 11 The gap between 27b and the truncated cone part 47 is quite large. For this reason, the intake amount of the blow-by gas B to the intake pipe side is considerably large, and the amount of fresh air introduced is correspondingly controlled.

  Next, when the internal combustion engine is stopped, no negative pressure is generated on the intake pipe side, so the regulating valve element 41 is not pulled toward the intake pipe side. For this reason, the regulating valve body 41 is pressed against the inflow side by the urging force of the spring 51. Accordingly, the flange 44 fixed to the intake side distal end portion 43 of the adjustment valve body 41 comes into contact with the outflow side surface of the convex portion 27 of the valve body 11 as shown in FIG.

  At this time, as shown in FIG. 4, the flange 44 has a bead 44 a protruding in an annular shape pressed against the surface on the outflow side of the convex portion 27, or the convex portion as shown in FIG. 5. Since the bead 27 a projecting in an annular shape on the outflow side surface of 27 is pressed by the flange 44, it comes into close contact with the convex portion 27 of the valve body 11. As a result, the gap between the flange 44 and the convex portion 27 of the valve body 11 is reliably sealed, so that the blow-by gas B on the intake pipe side flows back to the suction side through the flow-by gas passage 11 a of the valve body 11. Be blocked. That is, in the past, the inflow side end portion 42 of the regulating valve body 41 closed the inlet 12 of the lid portion 17 of the valve body 11 and acted as a check valve. However, in the present invention, the flange 44 is reversed. Acts as a stop valve.

  Here, by adjusting the elastic force of the spring 51, the fixing position of the flange 44, and the like, in a state where the flange 44 of the adjustment valve body 41 is in contact with the convex portion 27 of the valve body 11, the adjustment valve body 41 As shown in FIG. 10, the inflow side end portion 42 is set so as to be slightly separated from the lid portion 17 of the valve body 11.

Next, the operation of the PCV valve 1 of this embodiment will be described.
The PCV valve 1 includes a valve main body 11 through which blow-by gas B flows, an adjustment valve body 41 that is reciprocally movable inside the valve main body 11, and an inflow side end 42 of the adjustment valve body 41. And a spring 51 that urges the valve body 11 toward the inlet 12, so that when the internal combustion engine is operating, the peripheral corner portion 27 b of the convex portion 27 of the valve body 11 and the adjustment valve body 41 The truncated cone portion 47 functions as a throttle valve that adjusts the flow passage area of the blow-by gas B according to the negative pressure on the intake pipe side. As a result, the blow-by gas B is forcibly introduced to the intake pipe side and reduced downstream of the throttle valve, and the intake amount of the blow-by gas B and the introduction amount of fresh air are automatically set according to the operating state of the internal combustion engine. Controlled. As a result, the amount of blow-by gas B sucked in according to the operating state of the internal combustion engine is controlled, so that the blow-by gas B reduced downstream of the throttle valve is recombusted, so that the oil contained in the blow-by gas B The amount of O taken away is reduced.

  Further, in the PCV valve 1 of the present invention, the flange 44 capable of closing the blow-by gas passage 11a is provided at the intake-side tip portion 43 of the regulating valve body 41. The blow-by gas B is prevented from flowing backward from the intake pipe toward the crank chamber when the engine is stopped or backfired.

  In combination with this, the oil mist contained in the blow-by gas B flows while the blow-by gas B flows through the valve body 11 during the operation of the internal combustion engine. The PCV valve 1 according to this embodiment has a drain hole 30 provided at the lowermost portion 29 of the inner wall 14 of the valve body 11. Therefore, the oil O staying at the bottom portion 28 of the valve body 11 is discharged from the drain hole 30 by its own weight and returned to the crank chamber. As a result, the oil O is discharged to the intake pipe side to be recombusted and the consumption of the oil O is suppressed, and the occurrence of deposits in the intake pipe is suppressed.

  In addition, since the PCV valve 1 is provided with positioning means including the positioning portion 18 a of the flange portion 18 of the valve body 11 and the positioning rib 61 a of the cylinder head cover 61, the drain hole 30 is disposed on the inner wall 14 of the valve body 11. It can be easily and reliably positioned on the lower portion 29. Thus, the entire amount of the oil O staying at the bottom portion 28 of the valve body 11 can be naturally dropped from the drain hole 30 by its own weight and discharged, and returned to the crank chamber.

  By the way, as shown in FIG. 1, the drain hole 30 of the above embodiment is provided with a step 32 at the inflow side peripheral portion of the bottom portion 28 of the inner wall 14 of the valve body 11, and a discharge passage 33 is formed at the bottom portion 28. However, as shown in FIG. 11, the discharge passage 33 may be formed by providing a slope 34 in the peripheral portion on the inflow side of the bottom portion 28 of the inner wall 14 of the valve body 11. Also in this case, the oil O staying at the bottom portion 28 of the valve body 11 can be smoothly discharged from the drain hole 30.

  In addition, the drain hole 30 of the above embodiment is formed across the through hole 31 provided at the lower end portion of the lid portion 17 and the discharge passage 33 in the inflow side peripheral portion of the bottom portion 28 of the inner wall 14. As shown in FIG. 12, the inlet 12, the through hole 31 and the discharge passage 33 are formed as a drain part integrally communicating with each other. Also good. In this case, the drain portion functions as the inlet 12 of the blow-by gas B and also functions as the drain hole 30 for discharging the oil O staying at the bottom portion 28 of the valve body 11. Here, the discharge passage 33 of the valve main body 11 may be formed with a step 32 as in the case of the drain hole 30 shown in FIGS. 1 and 2, or may have a slope 34 as shown in FIG. It may be provided.

<Second embodiment>
Next, the PCV valve 1 according to the second embodiment of the present invention will be described with reference to the drawings. Note that the second embodiment will be described with a focus on differences from the first embodiment.

  In the valve body 11 of the second embodiment, the drain hole 30 is formed by a circular, elliptical, rectangular or other through hole 31 and, as shown in FIGS. A plurality of peripheral walls are provided at equal intervals in the circumferential direction at regular intervals. In FIG. 13 and FIG. 14, four are provided at regular intervals of 90 degrees. Therefore, even if the PCV valve 1 is attached to the cylinder head cover 61 via the grommet 63 in any direction without paying special attention to the position where the drain hole 30 is formed, any one of the plurality of drain holes 30 is always attached to the valve body 11. Located in the vicinity of the lowermost portion 29 of the inner wall 14.

  The valve main body 11 is fixed to a cylinder head cover 61 installed in the middle of the blow-by gas passage via a grommet 63 as a fixture. However, in the first embodiment, positioning means including the positioning portion 18a and the positioning rib 61a is provided, but in the second embodiment, no positioning means is provided. That is, as shown in FIG. 15, the flange portion 18 and the grommet 63 of the valve body 11 are formed in a circular shape as a whole. Of course, the positioning rib 61 a is not formed on the cylinder head cover 61. As described above, the valve body 11 is provided with a plurality of drain holes 30, and even if the PCV valve 1 is attached to the cylinder head cover 61 in an arbitrary direction, any one of the drain holes 30 is always attached to the inner wall 14 of the valve body 11. This is because there is no need to provide positioning means for positioning the drain hole 30 at the lowermost portion 29 of the valve body 11 since the lowermost portion 29 is located near the lowermost portion 29.

  As a result, the shapes of the valve main body 11 and the grommet 63 are simplified and easy to manufacture, and the position of the drain hole 30 does not have to be special, so that the assembly of the PCV valve 1 to the cylinder head cover 61 is facilitated. .

  In addition, as shown in FIG. 16, the drain hole 30 of 2nd embodiment is good also as what provided the plurality of the long holes 35 which penetrated the inner and outer walls and extended in the circumferential direction at predetermined intervals in the circumferential direction. In this case, since the drain hole 30 is long in the circumferential direction, the drain hole 30 can be more reliably positioned at the lowermost portion 29 of the inner wall 14 of the valve body 11.

  Further, although the drain hole 30 is provided in the peripheral wall in the peripheral portion on the inflow side behind the lid portion 17 of the valve body 11, a plurality of the drain holes 30 may be provided in the lid portion 17 of the valve body 11. That is, in the PCV valve 1 shown in FIG. 17, four drain holes 30 are provided in the lid portion 17 at equal intervals in the circumferential direction. In FIG. 17, the plurality of drain holes 30 communicate with the central inlet 12 of the lid portion 17, and the lid 17 has one large inlet 12 and the plurality of drain holes 30. It is formed in the drain part of the opening. However, the plurality of drain holes 30 and the central inflow port 12 may be separated from each other and formed independently.

<Third embodiment>
Next, a PCV valve 1 according to a third embodiment of the present invention will be described with reference to the drawings. Note that the third embodiment will be described with a focus on differences from the first embodiment and the second embodiment.

  The valve body 11 of the first embodiment and the second embodiment is attached to the cylinder head cover 61 via the grommet 63, but the valve body 11 of the third embodiment is as shown in FIGS. It is formed integrally with the cylinder head cover 61. In the integration, the valve body 11 is set so that the drain hole 30 is positioned at the lowermost portion 29 of the inner wall 14.

  The drain hole 30 is provided with a discharge passage 33 by providing a step 32 shown in FIG. 18 or an inclination 34 shown in FIG. 19 in the peripheral portion on the inflow side of the valve main body 11, similarly to the drain hole 30 of each embodiment. Can do. Further, the drain hole 30 can be provided at the lowermost end portion of the lid portion 17 so as to be separated from the inflow port 12, or can be integrated with the inflow port 12 and provided as one drain portion.

  Since the PCV valve 1 of the third embodiment is integrated with the cylinder head cover 61, when these are attached to the internal combustion engine, the drain hole 30 is inevitably accurately and reliably the lowermost portion 29 of the inner wall 14 of the valve body 11. Located in.

  By the way, the PCV valve 1 of each of the above embodiments is attached to the downstream side of the cylinder head cover 61 via the grommet 63. However, the present invention is not limited to this position. The blow-by gas passage between the chamber and the intake pipe can be attached at an appropriate position. For example, although not shown, the PCV valve 1 may be mounted in the horizontal direction on the downstream side of the engine body such as a cylinder block. An intake pipe is connected to the downstream side of the PCV valve 1.

Moreover, the PCV valve 1 of each said embodiment has shown the thing of the type installed sideways in a blow-by gas passage . As the PCV valve 1 of the reference example , a type that is installed in the blow-by gas passage in a vertical direction is exemplified , although not shown. In the vertically oriented PCV valve 1, when the suction side of the valve body 11 is downward, the inlet 12 of the lid portion 17 is located at the lower end. Accordingly, since the inlet 12 also serves as the drain hole 30, it is not necessary to provide the drain hole 30 in the lid portion 17 separately from the inlet 12, and it is also necessary to provide the discharge passage 33 in the inner wall 14 of the valve body 11. Absent. However, of course, the drain hole 30 may be provided separately from the suction port. Even in this case, the flange 44 of the adjustment valve body 41 is necessary.

  Furthermore, although the PCV valve 1 is attached to the downstream side of the cylinder head cover 61 adjacent to the PCV valve 1, the PCV valve 1 may be installed at a position or a place away from the cylinder head cover 61.

  In the above embodiment, the oil O staying at the bottom portion 28 of the valve body 11 is naturally dropped from the drain hole 30 by its own weight and discharged, but forcibly after the internal combustion engine is stopped by a separate suction means or the like. You may make it discharge from the drain hole 30. FIG.

  In addition, the valve body 11 of the above embodiment is attached to the cylinder head cover 61 using the grommet 63 as an attachment, but may be attached using other attachments such as screws.

  The foregoing examples are for illustrative purposes only and are not to be construed as limiting the invention. Although the invention has been described with reference to exemplary embodiments, it is to be understood that the language used in the description and illustration of the invention is illustrative and exemplary rather than limiting. As detailed herein, changes may be made in its form within the scope of the appended claims without departing from the scope or spirit of the invention. Although specific structures, materials and examples have been referred to in the detailed description of the invention herein, it is not intended to limit the invention to the disclosure herein, but rather, the invention is claimed. It covers all functionally equivalent structures, methods and uses within the scope.

  The present invention is not limited to the embodiments described in detail above, and various modifications or changes can be made within the scope of the claims of the present invention.

  The present invention is widely used as a technique related to a PCV valve that can return oil in the valve body to the crank chamber when the internal combustion engine is stopped.

  DESCRIPTION OF SYMBOLS 1; PCV valve, 11; Valve body, 12; Inlet, 13; Outlet, 14; Inner wall, 18a; Positioning part, 27; Convex part, 29; Bottom part, 30: Drain hole, 41; 42; Inlet side end portion, 43; Inlet side tip portion, 44; Flange, 51; Spring, 61; Cylinder head cover, 63; Grommet, B; Blow-by gas, O;

Claims (6)

A PCV valve provided in a blow-by gas passage connecting the crank chamber of the internal combustion engine and an intake pipe, and adjusting the flow rate of the blow-by gas in accordance with the operating state of the internal combustion engine;
A tubular valve body having a flow path for the blow-by gas formed therein and having an inlet and an outlet for the blow-by gas;
An adjusting valve body disposed in the valve body so as to be reciprocally movable;
A spring for biasing the inflow side end of the regulating valve body toward the inlet side of the valve body,
A flange capable of closing the flow path of the blow-by gas in contact with a convex portion provided on the inner wall of the valve body is provided at the front end of the intake side of the adjustment valve body,
The valve body is provided in the blow-by gas passage so that the axial direction thereof is lateral.
The valve body is provided with a drain hole for returning oil in the valve body to the crank chamber when the internal combustion engine is stopped .
The PCV valve , wherein the drain hole includes a groove-shaped discharge passage formed by providing a step or an inclination at the bottom of the inner peripheral wall of the valve body . 2. The PCV valve according to claim 1, wherein the drain hole is provided at an axial inflow side end portion of the valve body and is spaced downward from the blow-by gas inlet . 3.   3. The PCV valve according to claim 1, wherein an annular bead that protrudes toward the other contact surface is provided on one contact surface of the convex portion and the flange. The valve body can be attached to a passage forming portion that forms the blow-by gas passage via a fixture,
The positioning means for positioning so that the drain hole is positioned at the lowest part of the valve body is provided between the valve body and the passage forming portion. PCV valve. The valve body can be attached to a passage forming portion that forms the blow-by gas passage via a fixture,
The PCV valve according to any one of claims 1 to 3, wherein a plurality of the drain holes are provided at regular intervals of a predetermined angle along a circumferential direction centering on an axis of the valve body.   The PCV valve according to any one of claims 1 to 3, wherein the valve body is provided integrally with a passage forming portion that forms the blow-by gas passage.

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