JP2013029082A - Butterfly valve device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a butterfly valve device for an internal combustion engine contributable to safety operation of the engine, by preventing generation of rust in a bearing by a condensate, without reducing strength of a valve element, by forming a plurality of grooves capable of gathering the condensate to a central part while gaining the surface area of the valve element, only to an upstream side half area positioned on the upstream side of the valve element of forming a butterfly type valve.SOLUTION: A plurality of V-shaped condensate draining grooves 35 each having a top part toward the downstream side, are arranged on the downstream side from the upstream side, only on a surface 32a and a reverse surface 32b in the upstream side half area 32A of the valve element 32. Thus, even if the condensate including an acid component sticks to the valve element 32, since it is gathered and drained to the central part from a peripheral edge part of the valve element 32 by the grooves 35, the condensate does not infiltrate into bearings 8 and 9 for supporting a shaft 33, and the generation of rust of the bearings 8 and 9 can be prevented. Since only one side half of the valve element 32 is utilized, the whole strength of the valve element 32 is not impaired.

Description

  The present invention relates to a butterfly valve device which is used in an internal combustion engine (hereinafter referred to as an engine) mounted on a vehicle such as an automobile, and more particularly to directly control the amount of air taken into a combustion chamber of an engine. The present invention relates to a valve device in which a butterfly valve (butterfly valve) is employed as a valve body.

(Conventional technology)
A wide variety of butterfly valve devices of this type are in practical use. A typical example of the throttle valve device for intake control will be briefly described with reference to FIG. FIG. 1 schematically shows an intake / exhaust system of the engine 1. The intake passage 2 that leads combustion air toward the combustion chamber 1 a of the engine 1 is opened / closed or opened. A throttle valve device 3 for adjusting the degree is provided. The throttle valve device 3 includes a housing 31 that forms a part of the intake duct 4, a valve body 32 that forms a plate-like butterfly valve, and a shaft 33 that rotates the valve body 32. The passage area of the intake passage 2 is increased or decreased according to the operating conditions, and the amount of intake air flowing as shown by the arrow A, that is, the intake air amount of the engine 1 is controlled.

Then, depending on the operating conditions, the engine 1 may have a so-called backfire, that is, a backflow of combustion gas accompanied by a flame from the downstream side of the intake passage 2 (downstream side of the intake air) to the upstream side of the intake passage 2 (upstream side of the intake air) as indicated by an arrow B In some cases, the intake passage 2 may be filled with high-temperature and high-pressure combustion gas from the backfire.
In addition, as a countermeasure for exhaust gas purification, a part of the exhaust gas is positively introduced from the exhaust pipe 7 through the exhaust gas recirculation path 80 to the intake passage 2, particularly the downstream side of the throttle valve device 3. In many cases, an EGR device for re-combustion is attached. Specifically, an exhaust gas recirculation control valve device 90 is disposed in the exhaust gas recirculation path 80, and the valve device 90 is provided with a housing 91 and a butterfly valve as in the throttle valve device 3 described above. A butterfly valve device including a valve body 92 and a shaft 93 is used.
Thus, combustion gas (exhaust gas) always exists around the butterfly valve device, and the valve bodies 32 and 92 are exposed to the atmosphere of such gas.

(Problems of conventional technology)
However, in the butterfly valve device configured as described above, the shafts 33 and 93 are caused by the fact that an acidic component (component that promotes rusting) such as sulfurous acid gas is included in the combustion gas (exhaust gas). The bearings that support the housings 31 and 91 rust in a relatively short period of time, causing a problem that the valve bodies 32 and 92 rotate poorly.
That is, it is known that bearings made of metal, particularly iron-based materials, rust due to the coexistence of water and air, but after the engine 1 is stopped, the air staying around the valve devices 3 and 90 is cooled. As a result, the condensed water adheres to the surfaces of the valve bodies 32 and 92, and the condensed water travels through the shafts 33 and 93 and collects around the bearings via the gaps between the shafts 33 and 93 and the housings 31 and 91. Since this condensed water contains an acidic component in the combustion gas (exhaust gas), rusting of the bearing is further promoted, and it occurs before the valve bodies 32 and 92 rotate poorly in a short period of time. It turned out to rust.
When such a situation occurs, the amount of intake air by the valve bodies 32 and 92 becomes uncontrollable, which may lead to a fatal defect that suddenly hinders safe operation of the engine 1, and a solution is urgently required. It is desired.

  On the other hand, in this type of butterfly valve device, research and development has been repeated in order to avoid the situation where the valve body cannot be rotated due to icing of condensed water, and various proposals have been made as means for preventing this icing. Has been made. As a relatively simple structure, for example, as shown in Patent Document 1, recesses are formed on both the front and back surfaces of the valve body so that water droplets (condensed water) flow from the upper half side region to the lower half side region. In some cases, a storage wall is installed upright to collect water droplets collected in the lower half area.

Therefore, it is conceivable to apply such a structure for preventing freezing as a means for preventing the rusting of the bearing described above, but since the following problems are conceived, it cannot be put into practical use. Is the current situation.
(1) Since the idea is to collect water droplets (condensed water) on the valve body by the storage wall, the accumulated condensed water may enter the bearing due to engine vibration or the like.
(2) Since the recess is formed over the entire front and back of the valve body, the plate thickness of the valve body is substantially reduced, and the strength of the valve body itself is a concern.

  As described above, the problem of rusting in the butterfly valve device has been described in detail using a typical example of an intake control throttle valve device and an exhaust gas recirculation control valve device. There is a tendency to install a tumble valve device or a swirl valve device for changing the intake flow from each branch pipe 4a of the duct 4 to the intake port 1b of each cylinder to a more suitable flow. Also in these valve devices, when a butterfly type valve must be adopted as the valve body, there is a completely similar problem with respect to the influence of bearing rusting by condensed water containing acidic components.

  The present inventors have conducted various experiments and researches in order to find out such a problem. By skillfully utilizing the half region of the valve body forming the butterfly valve, particularly the half region located on the upstream side, It has been found that condensed water can be drained effectively without reducing the strength of the valve body.

JP 2002-4893 A

  The present invention has been made in view of the above investigation results, and the purpose thereof is to increase the surface area of the valve body only in the half region located upstream of the valve body constituting the butterfly valve. An internal combustion engine that contributes to the safe operation of the engine by preventing the bearing from rusting by reducing the strength of the valve body by reducing the strength of the valve body by forming multiple grooves that can collect the condensed water in the central part. An object is to provide a butterfly valve device for an engine.

[Means of claim 1]
According to the first aspect of the present invention, the valve body as a whole is supported by the shaft near the center, and forms a plate-like butterfly valve having a front surface and a back surface on both sides in the plate thickness direction. Has an upstream half area located upstream from the shaft and a downstream half area located downstream from the shaft when the intake passage is opened. A plurality of V-shaped grooves for condensate drainage having apexes toward the downstream side are arranged only on the front and back surfaces of the upstream half region, from the upstream side to the downstream side.

By adopting such a configuration, the condensed water adhering to the valve bodies is guided by the V-shaped grooves in each row and gradually flows down toward the top, that is, gathering at the central portion of the valve bodies. Combined with the fact that the self-weight fall effect is increased by collecting water, the condensed water can be drained well from the central portion of the valve body, in other words, the central portion of the intake passage.
Moreover, since the groove | channel for several condensed water drainage increases the total surface area of a valve body substantially, and increases the trapping amount of condensed water, the drainage effect is further promoted.
Therefore, it is possible to prevent the condensed water from entering the bearing side.
In addition, the region where the groove for condensate drainage is provided is only half of the valve body, and the shape of the groove itself is V-shaped with a top on the downstream side, so the strength of the valve body itself is also high strength Can be maintained.

[Means of claim 2]
According to the second aspect of the present invention, the plurality of grooves for condensate drainage are provided with communication paths for communicating top portions of adjacent grooves with each other.
With such a configuration, the condensed water adhering to each groove can be smoothly and smoothly flowed down from the upstream side to the downstream side, and the water collecting / draining effect of the condensed water can be further promoted.

[Means of claim 3]
According to the third aspect of the present invention, the shaft has a V-shaped concave surface for guiding condensed water that communicates with a groove for draining condensed water on the outer peripheral surface on the upstream half region side of the valve body. The V-shaped concave surface has a V-shape that extends along the axis of the shaft and is inclined toward the axial center toward the center of the shaft.
With such a configuration, the condensed water adhering to the upstream half region of the valve body can be reliably collected and drained at the central portion of the shaft.

[Means of claim 4]
According to invention of Claim 4, the shaft is provided with the flow path which connects each surface and back surfaces of the upstream half area | region and downstream half area | region of a valve body, It is characterized by the above-mentioned. .
With this configuration, the condensed water adhering to the upstream half region of the valve body can be surely flowed down to the downstream half region of the valve body through the flow passage and drained. Therefore, the condensed water does not stay on the valve body.

[Means of claim 5]
According to invention of Claim 5, the valve body is provided with the semi-annular groove | channel for condensed water drainage extended in the circumferential direction only in the peripheral surface of the plate | board thickness direction in an upstream half area | region. It is said.
With such a configuration, the condensed water adhering to the circumferential surface of the valve body in the plate thickness direction can also be collected and drained. Therefore, it is possible to prevent the condensed water traveling along the peripheral surface of the valve body from entering the bearing side.

[Means of claim 6]
According to the invention described in claim 6, the valve body is provided with through holes for opening both end portions of the semicircular groove for draining the condensed water on the circumferential surface in the plate thickness direction in the downstream half region. It is characterized by being.
By adopting such a configuration, the condensed water adhering to the circumferential surface in the plate thickness direction of the upstream half region of the valve body can surely flow down to the downstream half region of the valve body and be drained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a general engine provided with an intake device and an exhaust device as an engine for applying a butterfly valve device of the present invention, partially in vertical section. It is a typical cross-sectional view which shows the principal part of the butterfly valve apparatus of Example 1 of this invention in a partial cross section. FIG. 3 is an explanatory view of the shape of a V-shaped groove arranged on the valve body of the butterfly valve device shown in FIG. 2, and (a) and (b) are enlarged cross-sectional views taken along line XX in FIG. 2. It is a longitudinal cross-sectional view with which it uses for detailed description of the shaft and bearing part of the butterfly valve apparatus shown in FIG. It is a partial cross-section enlarged view with which it uses for description of the form of the peripheral part of the valve body of the butterfly valve apparatus shown in FIG. It is a typical cross section which shows the principal part of the butterfly valve apparatus of Example 2 of this invention in a partial cross section.

  The form for carrying out the present invention is to use the characteristics of a valve body that forms a butterfly type valve to effectively drain condensed water without reducing the strength of the valve body. This was realized by arranging a plurality of V-shaped grooves for condensate drainage having a peak toward the downstream side only on the front and back surfaces of the side half region from the upstream side to the downstream side.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted.

[Example 1]
FIGS. 1 to 5 are for explaining the first embodiment of the present invention. First, the basics of a general engine in which the butterfly valve device is applied as a throttle valve device for intake control based on FIG. After the outline of the configuration, the butterfly valve device according to the first embodiment will be described in detail with reference to FIGS.

(Description of applicable engine 1)
The engine 1 is mounted on a vehicle such as an automobile, and the intake passage 2 that guides combustion air toward the combustion chamber 1a of the engine 1 serves as a butterfly valve device to open / close or open the intake passage 2. A throttle valve device 3 that performs adjustment is provided. The throttle valve device 3 is basically interposed in the intake duct 4 and is housed in the outer casing 31 and is accommodated in the housing 31 so as to partition the upstream side and the downstream side of the intake passage 2. And a shaft 33 for rotating the valve body 32, and the flow passage area of the intake passage 2 is increased / decreased according to the operating conditions of the engine 1, and the intake air as indicated by the arrow A The flow (the intake air amount of the engine 1) is controlled.

  The engine 1 is normally composed of multiple cylinders, and the combustion chamber 1a of each cylinder is connected to each branch pipe 4a of the intake duct 4 via the intake port 1b. An air filter 5 is provided at the air intake 4b of the intake duct 4, and the air purified by the air filter 5 flows as indicated by an arrow A and is guided to the combustion chamber 1a. A passage from the air intake 4b of the intake duct 4 to the intake port 1b forms the intake passage 2 described above.

  Each branch pipe 4a of the intake duct 4 is provided with a fuel injection valve 6, and a mixture of fuel and air injected from the fuel injection valve 6 is introduced into the combustion chamber 1a via the intake valve 1c. The gas ignited and burned by the spark plug 1d is discharged from the exhaust port 1f to the exhaust pipe 7 through the exhaust valve 1e.

  In order to purify the exhaust gas, the engine 1 actively introduces a part of the exhaust gas from the exhaust pipe 7 through the exhaust gas recirculation path 80 to the intake passage 2, particularly downstream of the throttle valve device 3. Then, there is a tendency to install an EGR device that burns again. Specifically, the downstream side of the throttle valve device 3 in the intake passage 2 and the exhaust pipe 7 are connected by an exhaust gas recirculation path 80, and an exhaust gas recirculation control valve device 90 is interposed in the exhaust gas recirculation path 80. Is done.

  The exhaust recirculation control valve device 90 is also a butterfly valve device, and has the same basic structure as the throttle valve device 3, that is, a housing 91 that forms part of the exhaust recirculation path 80, and is accommodated in the housing 91. As a butterfly type valve, it has a basic structure consisting of three members: a plate-like valve body 92 that opens and closes the exhaust gas recirculation path 80 or adjusts the opening thereof, and a shaft 93 that rotates the valve body 92. . As described above, when the EGR device is mounted on the engine 1, the exhaust gas recirculation path 80 also controls intake air to the engine 1 even though it is exhaust gas.

(Detailed description of throttle valve device 3)
The throttle valve device 3 is disposed in the intake duct 4 that forms the intake passage 2 as described above. As shown in FIG. 2, the cylindrical housing 31 that constitutes a part of the intake duct 4, and the intake passage 2, a resin valve body 32 that opens / closes or adjusts the opening of the intake passage 2 and is rotatably supported by the housing 31, and the valve body 32 is operated to rotate inside the intake passage 2. A metal shaft 33 is provided as a basic configuration.

  The valve body 32 as a whole has a disk shape corresponding to the cross-sectional shape of the intake passage 2, and has a front surface 32 a and a back surface 32 b on both sides in the plate thickness direction. Is supported by the shaft 33 in the vicinity of the center to constitute a butterfly valve. In the present embodiment, the valve body 32 and the shaft 33 are fixed to the slit 33a (see FIG. 4) formed through the shaft 33 in the radial direction from the upper side of FIG. Insertion is performed until the positioning projection 32c protruding from the surface 32a of the valve body 32 abuts against the shaft 33, and is fastened and fixed by an attachment screw 34.

  However, as a means for integrating both the valve body 32 and the shaft 33, for example, it can be easily manufactured (integrated) by an insert molding technique. At this time, by forming an uneven surface on the inner peripheral surface of the slit 33 a of the shaft 33 by a satin finish or the like, the resin valve body 32 can be firmly fixed to the metal shaft 33. In addition, as a resin material of the valve body 32, for example, a thermosetting resin such as PPS is used.

  When the intake passage 2 is opened (transition from the valve-closed state to the valve-open state), the valve body 32 has an upstream half region 32 </ b> A that is located upstream of the shaft 33 and a downstream side of the shaft 33. And a downstream half region 32B. And the groove | channel 35 for condensed water drainage is provided only in the upstream half area | region 32A of the valve body 32 over both surfaces of the surface 32a and the back surface 32b. The grooves 35 have a V shape having a peak on the downstream side, and are arranged in parallel in five rows from the upstream side to the downstream side in the upstream half region 32 </ b> A of the valve body 32. Of the five rows of grooves 35, the two upstream rows of grooves 35a, 35b are completely V-shaped, while the remaining three rows of grooves 35c, 35d, 35e are inverted C-shaped. Strictly speaking, it is not V-shaped and does not have a top portion, but in this embodiment, such a reverse C-shape is treated as a kind of V-shaped groove having a top portion on the downstream side.

  In the groove 35 for condensate drainage, the shape of the cross section (cross section perpendicular to the flow direction) of each of the grooves 35a to 35e is appropriately selected so that drainage is smoothly performed, and is shown in FIG. As shown in FIG. 3 (b), either a reverse-cylindrical shape recessed in a semicircular shape, or a sawtooth shape in which a downstream side is formed in a deep groove may be used. In any case, the plurality of grooves 35 for draining condensed water are effective in substantially increasing the total surface area of the valve body 32 and increasing the amount of condensed water trapped.

  Further, the valve body 32 is provided with a semicircular groove 36 for draining condensed water extending in the circumferential direction only on the circumferential surface in the plate thickness direction in the upstream half region 32A. The valve body 32 is provided with through holes 37 that open both end portions of the semi-annular groove 36 on the circumferential surface in the plate thickness direction in the downstream half region 32B. As shown in FIG. 5, the through-hole 37 has an inlet 37a that opens to the upstream half region 32A and an outlet 37b that opens to the downstream half region 32B.

As for the shaft 33, the outer peripheral surface located in the upstream half area | region 32A side of the valve body 32 is partially chamfered by the axial direction. This chamfered portion forms a V-shaped concave surface 38 for guiding condensed water that extends along the axis of the shaft 33 and is inclined toward the axial center toward the center of the shaft 33.
In addition, a flow passage 39 is provided in the central portion of the shaft 33 to communicate the front and back surfaces 32a and 32b of the upstream half region 32A and the downstream half region 32B of the valve body 32, respectively.
The flow passage 39 can be easily provided using a jig even when the valve body 32 and the shaft 33 are integrated by an insert molding technique.

  In this embodiment, the metal shaft 33 having the slit 33a and the V-shaped concave surface 38 is formed by machining a cylindrical metal rod (for example, stainless steel material or heat-resistant steel material). However, the shaft 33 can be made of resin in the same manner as the valve body 32. The valve body 32 has a groove 35, a semi-annular groove 36, and a through hole 37, and has a relatively complicated shape. However, the valve body 32 can be manufactured from a metal plate by pressing, cutting, or the like. It can also be.

Both end portions 33 b and 33 c of the shaft 33 are rotatably supported by the bulging portions 31 a and 31 b of the housing 31 via bearings 8 and 9, respectively, and one end portion 33 b is connected to the drive source 10. Is done. As is well known, the drive source 10 receives a control signal corresponding to the operating state of the engine 1 from an electronic control device (not shown) and rotates the shaft 33 to a predetermined position, and is constituted by a motor or the like.
A ball bearing is used as the bearing 8 and a plain bearing is used as the bearing 9. The bearings 8 and 9 are both made of an iron-based material such as stainless steel.

  Further, a seal cap 11 is fitted into the bulging portion 31b of the housing 31 that supports the other end portion 33c of the shaft 33 in order to maintain airtightness.

(Description of the valve device 90 for exhaust gas recirculation control)
In this embodiment, the detailed structure of the exhaust gas recirculation control valve device 90 is omitted, but it has the same detailed structure as the throttle valve device 3 described above.
That is, the valve element 92 having the upstream half region 92A and the downstream half region 92B has a V-shaped groove for condensate drainage having a top portion toward the downstream side on both the front and back surfaces only in the upstream half region 92A. (Corresponding to the grooves 35) are provided in five rows (corresponding to the grooves 35a to 35e) from the upstream side to the downstream side. The valve body 92 is provided with a groove 35, a semi-annular groove 36 and a through hole 37, and the shaft 93 is provided with a slit 33a and a V-shaped concave surface 38. The shaft 93 is supported on the housing 91 by a bearing (corresponding to the bearings 8 and 9) made of an iron-based material.

In the above configuration, the action and effect of the present invention that should be noted will be described below.
(Background of Example 1)
The engine 1 has a backfire depending on operating conditions. This backfire is a phenomenon in which incomplete combustion gas explodes and burns due to, for example, a shift in the opening / closing timing of the intake valve 1c of the engine 1 or a shift in the ignition timing by the spark plug 1d. In addition to the vicinity of the port 1b, the intake passage 2 may flow backward (in the direction of arrow B in FIG. 1) to reach the vicinity of the air filter 5.
Therefore, the throttle valve device 3, particularly the valve body 32, disposed in the intake passage 2 is exposed to high-temperature and high-pressure combustion gas.
Needless to say, the valve body 32 is exposed to the combustion gas leaking from the intake port 1b even during normal operation of the engine 1.

  Further, when an EGR device is mounted as a countermeasure for exhaust gas purification, a part of the exhaust gas is passed from the exhaust pipe 7 via the exhaust gas recirculation path 80 downstream of the throttle valve device 3 in the intake passage 2. Therefore, the exhaust gas recirculation control valve device 90, particularly the valve body 92, is also exposed to high-temperature and high-pressure combustion gas (exhaust gas).

Thus, combustion gas (exhaust gas) exists around the throttle valve device 3 and the exhaust gas recirculation control valve device 90, and the air stays around the valve devices 3, 90 after the engine 1 is stopped. As it cools, it adheres as condensed water to the surfaces of the valve bodies 32 and 92 that form a butterfly valve.
The fact that the condensed water causes rusting of the bearings supporting the valve bodies 32 and 92, and that the rusting is prevented by the present invention, the throttle valve device 3 on behalf of both valve devices 3 and 90. Will be described in detail as an example.

  Since the bearings 8 and 9 are made of an iron-based material, it is known that rusting occurs due to the coexistence of water and air. Further, between the both end portions 33b and 33c of the shaft 33 and the housing 31, in order to partition the housing portion of the bearings 8 and 9, in practice, as shown in FIG. However, the condensed water adhering to the front surface 32 a and the back surface 32 b of the valve body 32 travels on the outer peripheral surface of the shaft 33, and passes through the gap E between the shaft 33 and the housing 31 and around the bearings 8 and 9. Break into. Since this condensed water contains an acidic component in the combustion gas (exhaust gas), the rusting of the bearings 8 and 9 is promoted, resulting in a rusting result in a short period of time.

(Characteristics and effects of Example 1)
In order to solve the above problems, the following technique is employed in the throttle valve device 3 of the first embodiment.
In the valve body 32 to which the condensed water adheres, in the upstream half region 32A, five rows of grooves 35 are arranged on both surfaces of the front surface 32a and the back surface 32b in a downstream direction. Moreover, each groove 35 is formed in a V shape with the downstream side as the top. Therefore, the condensed water is guided to the grooves 35 in each row and flows down toward the top of the grooves 35 as indicated by an arrow C, that is, the condensed water flows down while gathering at the central portion of the valve body 32.
On the other hand, since the shaft 33 is provided with a V-shaped concave surface 38 on the outer peripheral surface facing the upstream half region 32A, the condensed water flowing down the grooves 35d and 35e located toward the end is also V-shaped. The central part of the valve body 32 gathers along the concave surface 38.

Thus, the condensed water collected at the central portion of the valve body 32 is combined with the fact that the effect of dropping its own weight is increased by the collected water, and the downstream side of the valve body 32 as shown by the arrow D through the flow passage 39 of the shaft 33. It surely flows down to the half area 32B. Then, it is sucked into the engine 1 together with the intake air passing through the intake passage 2. As described above, the condensed water is collected in the central portion, so that the condensed water is prevented from entering the gap E between the shaft 33 and the housing 31 and is drained well from the central portion of the intake passage 2 to the engine 1 side. be able to.
Moreover, since the groove | channel 35 for several condensed water drainage increases the total surface area of the valve body 32 substantially, and increases the trapping amount of condensed water, the drainage effect is further promoted.
Further, the upstream half region 32A of the valve body 32 is also provided with a semi-annular groove 36 on the circumferential surface, and a through hole 37 is connected to the semi-annular groove 36, so that it adheres to the circumferential surface of the valve body 32. The condensed water that flows is also guided by the semi-annular groove 36 and flows down to the downstream half region 32 </ b> B of the valve body 32 through the through hole 37. Therefore, the condensed water transmitted to the peripheral surface of the valve body 32 does not enter the gap E between the shaft 33 and the housing 31.
By the above, it can prevent reliably that condensed water permeates into the bearings 8 and 9 side.

  In addition, since the area | region which provides the groove | channel 35 for condensate drainage is only the half of the valve body 32, and the shape of the groove | channel 35 itself also has comprised the V shape which has a top part in the downstream, Even high strength can be maintained.

[Example 2]
FIG. 6 is for explaining the second embodiment of the present invention, and basically has the same structure as the throttle valve device 3 of the first embodiment shown in FIG. The structure has been changed.
In the present embodiment, among the V-shaped grooves 35, the upstream side three rows of grooves 35 a to 35 c are provided with communication paths 40 for communicating the tops of the adjacent grooves 35 with each other.

  According to the present embodiment, of the V-shaped grooves 35, the condensed water flowing down the three upstream rows of grooves 35 a to 35 c smoothly passes from the upstream side to the downstream side via the connecting path 40. Can flow down. Therefore, as compared with the first embodiment described above, the effect of collecting and draining condensed water adhering to the valve body 32 can be further promoted.

[Modification]
Although two embodiments have been described in detail above, the intent of the present invention is to utilize only the upstream half region 32A (92A) of the valve body 32 (92), and to condense condensed water into the peripheral portion of the valve body 32 (92). For example, a specific top structure of the V-shaped groove 35 for draining the condensed water provided in the valve body 32 and the cross-sectional shape thereof, the number of arrangement thereof, and a semi-annular groove. 36 and the cross-sectional shape of the communication path 40, and the structure of the V-shaped concave surface 38 and the flow passage 39 provided on the shaft 33 can be variously modified without departing from the spirit of the present invention. A modification example is illustrated below.

(1) The grooves 35a to 35e of the V-shaped groove 35 are continuously arranged from the upstream side toward the downstream side, but may be spaced from each other.
(2) The depth of each of the grooves 35a to 35e may be gradually increased from the peripheral portion of the valve body 32 toward the central portion in other words toward the top portion.
(3) The number of arrangement of the V-shaped grooves 35 can be appropriately selected according to the groove width of each groove. In FIG. 2, the left and right halves of the grooves 35a to 35e may be slightly shifted up and down to form a staggered pattern.
(4) The valve body 32 has a groove 35, a semi-annular groove 36, and a through hole 37, and takes a variation in shape into a relatively complicated structure as a whole. If it is made of resin, a complicated structure can be easily manufactured.
(5) When both the valve body 32 and the shaft 33 are made of resin, the valve body 32 and the shaft 33 can be integrally formed of a common resin material.
(6) In providing the V-shaped concave surface 38 for guiding condensed water on the shaft 33, the chamfering type is used in the above embodiment, but the groove for actively digging the V-shaped concave surface 38 for guiding condensed water. You may form by a model.

  Further, in the above-described example, the application example to the throttle valve device 3 and the exhaust gas recirculation control valve device 90 has been described in detail. In FIG. 1, from each branch pipe 4a of the intake duct 4 to the intake port 1b of each cylinder. The same applies to tumble valves and swirl valves installed in order to change the intake air flow to a more suitable flow as long as the structure of the valve body 32 is a butterfly valve having a shaft 33 in the center. be able to.

1 engine (internal combustion engine)
1a Combustion chamber 2 Intake passage 3 Throttle valve device (butterfly valve device)
8, 9 Bearing 31 Housing 32 Valve body (plate-like butterfly type valve)
32A Upstream half region 32B Downstream half region 32a Front surface 32b Back surface 33 Shaft 35 Condensate drainage groove 36 Semi-annular groove 37 Through hole 38 V-shaped concave surface 39 Flow path 40 Connection path 80 Exhaust gas recirculation path (intake path)
90 Valve device for exhaust gas recirculation control (butterfly valve device)
91 Housing 92 Valve body (plate-like butterfly valve)
93 Shaft

Claims (6)

A housing forming an intake passage communicating with the combustion chamber of the internal combustion engine;
A valve body that is arranged inside the intake passage so as to partition the upstream side and the downstream side of the intake passage, and adjusts the opening of the intake passage;
A shaft that is supported by the housing via a bearing and that rotates the valve body inside the intake passage.
The valve body, as a whole, is supported by the shaft near the center, forms a plate-like butterfly valve having front and back surfaces on both sides in the thickness direction, and when the valve body opens the intake passage, An upstream half region located upstream from the shaft, and a downstream half region located downstream from the shaft,
In the valve body, a plurality of V-shaped grooves for condensate drainage having apexes toward the downstream side are arrayed from the upstream side to the downstream side only on the front and back surfaces of the upstream half region. A butterfly valve device for an internal combustion engine. The butterfly valve device for an internal combustion engine according to claim 1,
A butterfly valve device for an internal combustion engine, characterized in that a plurality of grooves are provided with communication paths for communicating top portions of adjacent grooves with each other. The internal combustion engine butterfly valve device according to claim 1 or 2,
The shaft extends on the outer peripheral surface on the upstream half region side of the valve body along the axis of the shaft and is V-shaped for condensate guidance that is inclined toward the axial center toward the center of the shaft. A butterfly valve device for an internal combustion engine having a concave surface. The butterfly valve device for an internal combustion engine according to any one of claims 1 to 3,
An internal combustion engine butterfly valve device characterized in that the shaft is provided with flow passages that respectively connect the front and back surfaces of the upstream half region and the downstream half region of the valve body. The butterfly valve device for an internal combustion engine according to any one of claims 1 to 4,
A butterfly valve device for an internal combustion engine, characterized in that a semi-annular groove for condensate drainage extending in the circumferential direction is provided only on the circumferential surface in the plate thickness direction in the upstream half region of the valve body. The butterfly valve device for an internal combustion engine according to claim 5,
A butterfly valve device for an internal combustion engine, wherein the valve body is provided with through holes that open both end portions of the semi-annular groove on a circumferential surface in a plate thickness direction in the downstream half region.

Images