JP6604844B2 - Air intake duct structure - Google Patents

Description

  The present invention relates to an intake duct structure that guides air to an engine.

  As an intake device that introduces air into the engine, an intake duct having an intake port, an air cleaner that purifies the intake air introduced by the intake duct, a throttle valve that adjusts the amount of purified intake air (air) supplied to the engine, One having a surge tank and an intake manifold for distributing the adjusted air to each cylinder of the engine is known.

  If water such as water droplets is contained in the intake air drawn from the intake port and the water enters the cylinder of the engine, a water hammer phenomenon may occur and the engine may be damaged. Therefore, the moisture contained in the intake air is separated and discharged from the intake air by the intake duct or the air cleaner. For example, Patent Document 1 discloses that, as an intake duct installed in a vehicle such as a large truck, a large number of ribs are formed in an air box of the intake duct and a drain valve is provided at the bottom of the air box. . Moisture is separated from the intake air drawn from the intake port by collision with various ribs or vortex flow of the intake air. The separated moisture is guided to the bottom along the inner wall surface of the rib or air box, and is discharged to the outside from the drain valve.

JP-A-8-170567

  In the technique disclosed in Patent Document 1, even if the intake air collides with the roof-type rib formed above the outlet to the air cleaner and the water is separated in the air box of the air intake duct, the water is absorbed by the intake air flow. There is a risk of going to the exit to the air cleaner and passing through the exit.

  The present invention has been made in view of the above circumstances, and one of its purposes is to provide an intake duct structure capable of effectively discharging moisture in intake air to the outside.

  An intake duct structure according to one aspect of the present invention is an intake duct structure that guides air sucked from an intake port to an engine, and includes a first intake duct, a second intake duct, and a rib. The first intake duct has an intake port at the upper end and a drain hole at the lower end, and the second intake duct branches in the middle of the first intake duct and extends toward the air cleaner. The rib protrudes to the inner side of the first intake duct at a connection portion between the inner wall portion of the first intake duct and the inner wall portion of the second intake duct. The rib is continuously provided downward from the circumferential upper portion of the opening of the second intake duct, and the lower end thereof is positioned below the lower portion of the opening of the second intake duct. . The inner wall portion of the first intake duct includes an acute angle forming surface that forms an acute angle with the rib.

  The above intake duct structure has a rib at the opening of the second intake duct that branches to the air cleaner side in the middle of the first intake duct, so that the moisture flowing to the second intake duct side out of the moisture sucked from the intake port , Hits the rib, flows downward through the rib, and flows down from the lower end portion of the rib located below the lower portion of the second intake duct. Therefore, the water | moisture content which contacted the rib can be reliably guide | induced to the drain hole located in the lower end part of a 1st intake duct. In addition, by forming an acute angle between the first intake duct and the rib, moisture can be collected at the ridge line portion formed by the first intake duct and the rib. Therefore, moisture flows down along the ridge line portion of the rib, so that moisture is prevented from flowing over the free end side of the rib due to intake air flow, etc., and moisture is directed to the opening side of the second intake duct. We can prevent going. As described above, moisture in the intake air passes through the rib without passing through the opening of the second intake duct extending to the air cleaner side, and is discharged to the outside from the drain hole located at the lower end portion of the first intake duct.

FIG. 3 is an external schematic perspective view showing an arrangement state of the intake duct structure according to the first embodiment. It is a front view which shows the intake duct structure of FIG. It is arrow (III)-(III) schematic sectional drawing of FIG. It is arrow (IV)-(IV) schematic sectional drawing of FIG.

  An embodiment of an intake duct structure of the present invention will be described below with reference to the drawings. In the figure, the same reference numerals indicate the same names.

Embodiment 1
Overall Configuration As shown in FIG. 1, the intake duct structure 1 of the first embodiment is provided behind a vehicle compartment 110 provided above an engine (not shown) and a back panel 111 forming the vehicle compartment 110. The present invention is applied to a small truck 100 having a loading platform 120. Here, the loading platform 120 includes a bottom surface (deck panel), a side surface (side panel or side gate), and a rear surface (rear panel or rear gate), with the back panel 111 of the passenger compartment 110 as a front surface, these bottom surface, side surface, rear surface, It is formed to open upward by the front surface. An intake device that introduces air into the engine is disposed below the vehicle. The intake device introduces intake air through an intake duct, purifies the introduced intake air with an air cleaner (not shown), and purifies the intake air (air) with a throttle valve, a surge tank, and an intake manifold (all not shown) To supply to each cylinder of the engine. In the first embodiment, the intake duct structure including the intake duct is disposed above the loading platform 120. One of the features of the intake duct structure 1 according to the first embodiment is that the intake duct structure 1 is configured to effectively discharge moisture such as water droplets contained in the intake air introduced from the intake duct to the outside. Specifically, the intake duct structure 1 of the first embodiment is divided into a first intake duct 10 having an intake port 12 and a drain hole 14 as an intake duct, and extends in the middle of the first intake duct 10 to extend to the air cleaner side. A second intake duct 20. Then, a rib 30 is provided at a connection portion 30c between the inner wall portion of the first intake duct 10 and the inner wall portion of the second intake duct 20, and the acute angle forming surface 10s that forms an acute angle with the rib 30 on the inner wall portion of the first intake duct 10 is provided. Is provided. Details will be described below.

As shown in FIG. 1, the first intake duct 10 is arranged substantially along the back panel 111, and has an inlet 12 at the upper end and a drain hole 14 (FIGS. 2 and 3) at the lower end. Have As shown in FIGS. 1 and 2, the first intake duct 10 is curved in an inverted U shape on the upper end side thereof, and has a shape such that the intake port 12 opens downward in the vehicle. With this shape, the outside air can be efficiently sucked from the air inlet 12 and it is difficult to suck water droplets or foreign matters. In this example, the first intake duct 10 includes a flange 16 (FIGS. 1 and 2) that protrudes outward from the outer surface of the first intake duct 10 above the intake port 12. By providing the flange 16, it is difficult to inhale water droplets or the like from the intake port 12.

  The first intake duct 10 includes a curved portion from the upper end side toward the lower end side. Specifically, as shown in FIG. 3, the surface opposite to the side connected to the second intake duct 20 described later (the surface located on the right side in FIG. 3) is the vertical direction of the first intake duct 10. It is curved so as to swell toward the opposite side of the second intake duct 20 in the vicinity of the center (sometimes referred to as an outer curved portion). The surface connected to the second intake duct 20 (the surface located on the left side in FIG. 3) is opposite to the arrangement side of the second intake duct 20 from the upper end side of the first intake duct 10 to the vicinity of the central portion in the vertical direction. It is curved so as to swell to the side (sometimes referred to as an inner curved portion), and is substantially vertical from the vicinity of the center to the lower end. This substantially vertical surface portion is connected to the second intake duct 20. The lower end side of the first intake duct 10 has a smaller volume than the upper end side. The shape of the first intake duct 10 will be described in detail in the operation and effects described later.

  The drain hole 14 of the first intake duct 10 is opened downward, and water such as water droplets can be discharged to the outside, and foreign matter is difficult to enter the first intake duct 10 through the drain hole 14. The shape and dimensions are such that the drain hole 14 is not blocked.

Second Air Intake Duct As shown in FIG. 1, the second air intake duct 20 branches in the middle of the first air intake duct 10 in a direction intersecting the vertical direction and extends to the air cleaner side. In this example, the second intake duct 20 includes a curved portion extending from the connecting portion 30c (FIG. 3) to the first intake duct 10 to the rear of the vehicle and downward of the vehicle, and a short straight portion connected to the curved portion and extending downward of the vehicle. (See also FIG. 3), and is not directly connected to the air cleaner. A short straight line portion is a place where the rubber hose 50 (FIG. 1) is attached. The second intake duct 20 is connected to the connection duct 60 via the rubber hose 50, and the connection duct 60 passes through the bottom surface of the loading platform 120 and is connected to the air cleaner below the loading platform 120.

Ribs The rib 30 protrudes to the inner side of the first intake duct 10 at the connection portion 30c between the inner wall portion of the first intake duct 10 and the inner wall portion of the second intake duct 20 as shown in FIGS. It is a bowl-shaped part. As shown in FIG. 4, the rib 30 is continuous to the curved portion 32 provided continuously downward from the circumferential upper portion of the opening 22 of the second intake duct 20, and to both ends of the curved portion 32. And a pair of straight portions 34 extending downward from the lower portion of the opening 22 of the second intake duct 20. That is, the rib 30 has an inverted U-shape that is open to the lower portion by the curved portion 32 and the pair of linear portions 34. The rib 30 is disposed along the upper and side portions of the opening 22 of the second intake duct 20 in the circumferential direction, and the lower end is positioned below the lower portion of the opening 22, so It serves as a wall that prevents moisture from passing through the opening 22 of the second intake duct 20. The protruding length of the rib 30 can be selected as appropriate so long as moisture can be prevented from passing through the opening 22 of the second intake duct 20. The first air intake duct 10, the second air intake duct 20, and the rib 30 are integrally molded resin products.

  As shown in FIG. 3, the inner wall portion of the first intake duct 10 includes an acute angle forming surface 10 s that forms an acute angle with the rib 30. In this example, the rib 30 protrudes in the horizontal direction from the connecting portion 30c toward the inner side of the first intake duct 10, and the acute angle forming surface 10s is formed on the outer side of the first intake duct 10 (the second intake duct 20 side). ). In this example, the acute angle forming surface 10s is a curved surface, but may be a flat inclined surface.

Others In the first embodiment, the intake duct structure 1 is fixed to the back panel 111 by the fixing portion 80. In this example, the first intake duct 10 has the mounting piece 18 of the fixing portion 80, and the first intake duct 10 is fixed to the back panel 111 by the fixing portion 80. The intake duct structure 1 is covered with a protective cover 90. By providing the protective cover 90, it is possible to suppress inhalation of foreign matter from the intake port 12 and to protect the first intake duct 10 and the second intake duct 20. The protective cover 90 is preferably made of a member having the same strength as the back panel 111.

-Action The action of the intake duct structure 1 having the above configuration will be described with reference to FIGS.

  Of the intake air introduced from the intake port 12 (FIGS. 1 and 2) of the first intake duct 10, the air enters along the shape of the first intake duct 10 as shown by the solid line arrow in FIG. It hits the outer curved portion of the duct 10 and proceeds to the second intake duct 20 side that is located on the opposite side of the bulging direction of the curved portion. The air that has advanced to the second intake duct 20 side passes through the opening 22 of the second intake duct 20 and advances to the air cleaner side.

  The intake air introduced from the intake port 12 (FIGS. 1 and 2) of the first intake duct 10 contains moisture such as water droplets, and the moisture is on the opposite side of the first intake duct 10 from the arrangement side of the second intake duct 20. When a locus close to the surface is drawn, the moisture flows down to the lower end side of the first intake duct 10 and is discharged from the drain hole 14 as shown by a one-dot chain line in FIG. On the other hand, when the moisture draws a locus close to the surface on the arrangement side of the second intake duct 20 in the first intake duct 10, the moisture is an inner curved portion of the first intake duct 10 as shown by a two-dot chain line in FIG. 3. And flows down to the upper part of the rib 30 along the inner wall portion of the first intake duct 10. At this time, the moisture flows along the acute angle forming surface 10 s to the ridge line portion formed by the first intake duct 10 and the rib 30. As shown by the two-dot chain line in FIG. 4, the moisture that has flowed to the ridge line portion travels from the curved portion 32 of the rib 30 to the straight portion 34 and flows down from the lower end portion of the straight portion 34 to the lower end side of the first intake duct 10. The water is discharged from the drain hole 14 (FIG. 3).

Effect The intake duct structure 1 of the first embodiment includes a first intake duct 10 having an intake port 12 and a drain hole 14 and a second intake duct 20 extending to the air cleaner side, and the first intake duct 10 is curved outward. By providing the portion, the air in the intake air can flow to the second intake duct 20 side, and the water in the intake air can flow to the lower end side of the first intake duct 10. The connection portion 30c between the first air intake duct 10 and the second air intake duct 20 is provided with a rib 30 that has an inverted U-shape and a lower end located below the opening 22 of the second air intake duct 20 so that moisture can be contained. Even when a locus close to the surface on the arrangement side of the second intake duct 20 is drawn, the moisture hits the rib, so that the moisture can flow down to the lower end portion of the first intake duct 10 through the rib. In this example, by providing the inner curved portion in the first intake duct 10, when moisture draws a locus close to the surface on the arrangement side of the second intake duct 20, the moisture hits the inner curved portion. The hit water can be flowed down to the rib 30 along the inner wall surface of the first intake duct 10.

  In particular, since the first intake duct 10 and the rib 30 form an acute angle, moisture that has flowed down to the rib 30 can be collected in the ridge line portion formed by the first intake duct 10 and the rib 30, and the ridge line portion It is easy for water to flow down. For this reason, it is possible to prevent moisture from flowing over the free end side of the rib 30 (inside the first intake duct 10) due to an intake air flow or the like in the middle of the rib 30. Therefore, moisture can hardly be directed to the opening 22 side of the second intake duct 20, and moisture can be flowed down to the lower end side of the first intake duct 10. Since the acute angle forming surface 10s is closer to the outside of the first intake duct 10 (the second intake duct 20 side) than the upper side in the vertical cross section shown in FIG. Compared with the case where the angle formed by the ribs 30 is a right angle, the distance from the ridge line portion to the tip of the ribs 30 can be easily increased. Also from this, it is easy to suppress water from flowing over the rib 30 over the free end side of the rib 30. As described above, even when moisture such as water droplets is contained in the intake air introduced from the intake port 12, the moisture is effectively discharged outside without passing through the opening 22 of the second intake duct 20. be able to.

  Here, in the case of the small truck 100 provided with the passenger compartment 110 above the engine and the loading platform 120 at the rear of the passenger compartment 110, the intake device may have the following forms as the location of the intake port of the intake duct. (1) A hole is formed in the side member, an intake duct is attached to the side member, and an intake port is disposed opposite to the hole of the side member. (2) The air intake duct is extended to the front of the vehicle, and the air intake port is disposed opposite the bumper opening. (3) The air duct is exposed and extended along the back panel to the vicinity of the highest position of the passenger compartment. For each of the above forms, (1) In the case of flooding or flooding, there is a risk of flooding to the side members. Water enters the engine cylinder and water hammer phenomenon occurs when water enters the engine cylinder. There is a risk of damaging the engine. (2) In the case of a small truck, since the engine is arranged in the center of the vehicle, the duct length becomes long and the cost increases. Further, in the case of a small truck, it is difficult to dispose a duct due to positional restrictions with peripheral parts. (3) The duct length becomes long, resulting in high cost.

  Since the air intake duct structure 1 according to the first embodiment is arranged on the loading platform 120, even if the water volume is increased over the entire lower part of the vehicle due to flooding or flooding, the air intake structure as described in (1) above can be used. Intrusion of water can be prevented. Therefore, it can be suitably used even in an area that is frequently flooded during the rainy season, such as the Southeast Asian region. Moreover, since the intake duct structure 1 of the first embodiment is located on the loading platform 120, the duct length can be made relatively short compared to the above (2) and (3), and the cost is hardly increased.

  Further, in the intake duct structure 1 of the first embodiment, the volume of the first intake duct 10 is smaller on the lower end side than the upper end side, so that the pressure loss in the first intake duct 10 is larger on the lower end side than the upper end side. Moreover, since the rib 30 is provided in the first intake duct 10, the pressure loss in the first intake duct 10 is larger on the lower end side than on the upper end side. Therefore, even if the drain hole 14 located on the lower end side of the intake duct structure 1 (first intake duct 10) is immersed in water, the pressure loss in the first intake duct 10 is lower than the upper end side. Since the direction is larger, it is difficult for water to be sucked into the first intake duct 10 from the drain hole 14.

≪Modification≫
The present invention is not limited to these exemplifications, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims. For example, in Embodiment 1 described above, a description has been given of a mode in which the rib 30 protrudes from the connection portion 30c in the horizontal direction toward the inner side of the first intake duct 10, but the rib is located on the inner side of the first intake duct rather than the connection portion side. It can also project inclining so that it may be located above. In this case, the acute angle forming surface of the first intake duct may not be formed to extend to the outside of the first intake duct (second intake duct side), and may be, for example, a vertical surface. The first intake duct 10 and the rib 30 can form an acute angle because the rib is inclined so as to be upward toward the inner side of the first intake duct.

  In Embodiment 1 described above, the rib 30 has an inverted U-shape that is opened downward at the curved portion 32 and the pair of linear portions 34. However, the rib is the shape of the opening of the second intake duct. For example, an inverted V shape can be used. Moreover, it can also be set as the shape open | released by the lower part by the reverse V-shaped part and a pair of linear part continuous to the both ends of this reverse V-shaped part.

  Furthermore, in Embodiment 1 described above, the first intake duct 10 is disposed substantially along the back panel 111 and the lower end side (drainage hole 14) of the first intake duct 10 is also located on the loading platform 120. The lower end side of the first intake duct 10 may be positioned below the loading platform 120 through the loading platform 120.

  The intake duct structure of the present invention can be suitably used for an intake device that introduces air into an engine in a small truck. In particular, it can be suitably used for an air intake device installed in a small truck used in an area where countermeasures against flooding and flooding are desired.

DESCRIPTION OF SYMBOLS 1 Air intake duct structure 10 1st air intake duct 10s Acute angle formation surface 12 Air inlet 14 Drainage hole 16 Gutter part 18 Attachment piece 20 2nd air intake duct 22 Opening part 30 Rib 30c Connection part 32 Curved part 34 Straight part 50 Rubber hose 60 Connection duct 80 Fixed part 90 Protective cover 100 Light truck 110 Car compartment 111 Back panel 120 Loading platform

Claims (1)

An air intake duct structure that guides air sucked from the air intake port to the engine,
A first air intake duct having the air inlet at the upper end and a drain hole at the lower end;
A second intake duct that branches off in the middle of the first intake duct and extends toward the air cleaner;
A rib projecting to the inner side of the first intake duct at a connection portion between the inner wall portion of the first intake duct and the inner wall portion of the second intake duct;
The rib is continuously provided downward from the circumferential upper portion of the opening of the second intake duct, and the lower end thereof is positioned below the lower portion of the opening of the second intake duct. And
In the intake duct structure, an inner wall portion located on an upper portion of the rib in the first intake duct includes an acute angle forming surface that forms an acute angle with the rib.

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