Engine intake system

Abstract

To achieve improvement in silence effect and reduction of the pressure loss while reducing the size as a whole in an intake device constituted by a duct unit integrated with a resonator, and an air cleaner.SOLUTION: A duct unit 6 is formed by welding two front and rear shell-like members 21, 22, and includes an intake duct 23 formed in an almost U-shape, and resonators 24, 25 disposed in a space surrounded by the intake duct 23. A receiving plate 16 extending forward and rearward is integrally formed in an upper end of the duct unit 6, and a body case 7 of an air cleaner 5 is welded to the receiving plate 16. Since the intake duct 23 is formed in the almost U-shape, flow resistance of air is small. The resonators 24, 25 are enfolded by the intake duct 23, and therefore, the length of the intake duct 23 can be increased, and silence effect can be improved.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an intake device that is provided as an accessory to an engine (internal combustion engine). [Background technology]

[0002] In gasoline and diesel engines, air cleaners are essential to take in and purify the air. As an engine accessory, air cleaners have a relatively high degree of freedom in design, and a variety of structures and arrangements have been proposed.

[0003] For example, Patent Document 1 discloses that a resonator and an intake duct are integrally provided on the underside of a main body case that constitutes an air cleaner. Patent Document 2 also discloses that a resonator is integrally provided in a dirty chamber of an air cleaner. Integrating a resonator into an air cleaner as in Patent Documents 1 and 2 has the advantage of making the whole unit more compact while suppressing intake noise. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2000-064920 A [Patent Document 2] JP 2002-339822 A Summary of the Invention [Problem to be solved by the invention]

[0005] In order to improve the effect of eliminating intake noise, it is preferable to make the intake duct as long as possible, but since Patent Documents 1 and 2 have a limit to the length of the intake duct, it is understood that there is also a limit to the noise elimination effect.

[0006] In other words, in Patent Document 1, the intake duct is formed to surround the main body case from below, so the length of the intake duct is naturally limited by the size of the main body case.In Patent Document 2, the inside of the resonator case integrated into the dirty chamber is partitioned to form a U-turn or serpentine-shaped intake duct, but even in this case, the size of the resonator case is regulated by the size of the dirty chamber, so there is a limit to how long the intake duct can be made, and in either case, it is understood that there is a limit to the performance of eliminating intake noise.

[0007] In addition, if the intake duct is made to turn or snake as in Patent Document 2, the air may suddenly change direction, which may increase the air flow resistance, or the air may collide with the suddenly bent part and cause membrane vibration, which may negate the purpose of providing a resonator. In addition, in Patent Document 2, the volume of the space surrounded by the intake duct is small, so there is also the issue of whether the resonator can fully function.

[0008] Therefore, when considering an air cleaner equipped with an intake duct with an integrated resonator, it is required to make the length of the intake duct as long as possible while minimizing air flow resistance, and to arrange it compactly while securing the volume required for the resonator. In addition, air may contain dust and moisture, and it is preferable to prevent this dust and moisture from reaching the filter element of the air cleaner. Furthermore, strength (rigidity) must be ensured. In particular, in the case of an air cleaner mounted on an automobile, it is important to consider strength because it is subjected to vibrations caused by driving and engine vibrations.

[0009] The present invention was made in response to such circumstances, and aims to provide an improved intake device which has excellent noise reduction capabilities while suppressing flow resistance. [Means for solving the problem]

[0010] The present invention includes the features of claims 1 and 2. The invention of claim 1 is as follows: "It is equipped with an air cleaner, an intake duct that takes in air into the air cleaner, and a resonator that is integrally provided with the intake duct via a communication passage, The intake duct has a first vertically elongated section with an intake port opening at its upper end and through which air flows downward, a second vertically elongated section with an exhaust port opening at its upper end and through which air flows upward, and a bottom section connected to the lower ends of both vertically elongated sections, and a main body case constituting the dirty chamber of the air cleaner is integrally connected to the upper end of the second vertically elongated section. In this basic configuration, "The air cleaner is a bottom part of the intake duct in a plan view. Total length The resonator is disposed so as to overlap with the intake duct, while the resonator is disposed in a space surrounded by the two longitudinal portions and the bottom portion of the intake duct. only It is located in The air cleaner, the resonator, and the bottom of the intake duct are arranged at different heights so as to overlap each other in a plan view. It has the following characteristics:

[0011] On the other hand, the invention of claim 2 is as follows: In claim 1, "The intake duct is formed on the mating surface of the two shell-shaped members that are overlapped and joined together, and the first vertical portion, the bottom portion, and the second vertical portion are continuous with each other. A substantially horizontal receiving plate in which the discharge port of the second vertically elongated portion is opened is integrally provided on one of the two shell-shaped members, and the main body case of the air cleaner is fixed to the receiving plate. The structure is as follows. do.

[0012] Also in claim 1 The intake duct and resonator can be formed into a hollow structure by overlapping and joining two shell-shaped members made of synthetic resin. By adopting this joining structure, the intake duct with the resonator can be easily manufactured. do. Effect of the Invention

[0013] In both of the present inventions, the intake duct is substantially U-shaped with a first vertical portion, a bottom portion, and a second vertical portion, so that the air flow does not have to change direction suddenly, and the length of the intake duct can be increased while suppressing air flow resistance. More specifically, the first vertical portion is not restricted by the main body case, so the first vertical portion can be made longer than the second vertical portion, which ensures that the length of the intake duct can be increased and improves the design freedom for the position of the intake port. Furthermore, the air flows downward through the first vertical portion and then upward through the second vertical portion, so that dust, sand, and moisture can be prevented from entering the air cleaner. This improves the durability of the filter element.

[0014] In the invention of claim 1, the resonator is placed in the space surrounded by the intake duct, but since the intake duct has a bottom and the area of ​​the enclosed space is large, the length of the intake duct can be increased while effectively utilizing the space below the air cleaner, and the volume of the resonator can also be increased. Therefore, the resonator's function can be fully utilized, and the effect of eliminating noise and vibration can be significantly improved.

[0015] In addition, in the invention of claim 1, the air cleaner, intake duct, and resonator are unitized as a single intake device, so that when mounting the device to the engine body or vehicle body, the number of mounting points can be reduced, improving work efficiency. Claim 2 By joining two shell-shaped members together to make the intake duct and resonator hollow as shown in the figure, the resonator exerts a rib effect to reinforce the intake duct, thereby improving the overall rigidity.

[0016] It is also possible to connect the mid-height portions of the first and second vertical sections via a resonator. If this structure is adopted and applied to an automobile engine, even if the automobile drives on a flooded road and water accumulates at the bottom of the intake duct, causing it to become blocked, air can be taken in to the air cleaner and the engine can continue to operate.

[0017] As in claim 2, when the main body case of the air cleaner is fixed to the receiving plate that is integral with the intake duct, the space below the air cleaner is effectively utilized to make the intake device compact, and the intake duct can be stably suspended by the main body case of the air cleaner. (This also applies to claim 1.) In this case, the intake duct is made up of two overlapping shell-shaped members, and a support plate is integrally formed on one of the shell-shaped members, projecting from the top end on both sides. By doing Since the support plate and the shell-shaped member form a T-shaped structure, the rigidity can be improved significantly, which is preferable. In addition, by integrating the main case and the receiving plate by welding or the like, the bottom plate plane of the main case facing the ground has a double structure, which significantly reduces the radiated sound emitted from the surface of the air cleaner. As a result, when applied to a vehicle, the external noise heard on the side of the vehicle due to the radiated sound of the air cleaner being reflected by the ground is also suppressed. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view of the intake device as viewed from slightly obliquely above. [Diagram 2] FIG. 2 is a perspective view of the intake device as seen from below. [Diagram 3] FIG. [Figure 4] FIG. 2 is an exploded side view of the intake device (however, the right shell-shaped member is inverted). [Diagram 5] FIG. 2 is a separated side view of two shell-like members in an unfolded state (with mating surfaces exposed). [Figure 6] FIG. [Figure 7] FIG. 13 is a perspective view of the right shell-shaped member with some of the structure omitted. [Figure 8] FIG. 2 is a perspective view of the air cleaner as viewed from below. [Figure 9] 1A and 1B are diagrams showing an automobile to which an embodiment is applied, in which (A) is an overall side view, and (B) is an enlarged, partially cut-away view of (A). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Next, an embodiment of the present invention will be described with reference to the drawings. A cab-over van (for example, a minivan of one-box type) is shown in Fig. 9, and the intake device 1 of this embodiment can be mounted on this cab-over van.

[0020] That is, a cab-over van has a front compartment (driver's cab) 2 in which the front seats 2a are located, and a luggage space 3 behind it, with an engine 4 located in the space below the front seats 2a, but the intake device 1 of this embodiment is located in a portion below and behind the front seat 2a, closer to the passenger seat (the space surrounded by the vehicle body's side member (underframe), the floor and the underbody (outer panel)) (it may also be located on the side of the driver's seat).

[0021] The engine 4 is mounted vertically with the crankshaft facing the front-rear direction of the vehicle, and the cylinder bore axis is largely slanted so that it approaches the horizontal side. The intake side is also facing upward. In Fig. 6(B), 4a is the transmission case, and 4b is the drive shaft.

[0022] In the following, the terms "front, rear, left, right" are used to specify directions, but these directions are the same as the front, rear, left, right directions of a vehicle. In other words, they are the same as the front, rear, left, right directions as seen by the driver. Directions are indicated appropriately in each figure.

[0023] (1) Overview As shown in FIG. 1, the intake device 1 comprises an air cleaner 5 and a duct unit 6, the majority of which is located below the air cleaner 5. As shown in FIG. 4, the air cleaner 5 comprises a main body case 7 made of synthetic resin located at the bottom and having a dirty chamber, a cover case 8 made of synthetic resin that forms a clean chamber and overlaps the main body case 7 from above, and a filter element 9 sandwiched between the two.

[0024] The cover case 8 is in the form of a tray that opens downward, and each corner is fixed to the main case 7 by a substantially C-shaped clip 10. Therefore, the cover case 8 of this embodiment is detachable. Therefore, an enclosure-shaped edge body 11a is integrally formed on the outside of the opening edge of the cover case 8, and the clip 10 is hooked on the edge body 11a against elasticity. In addition, an exhaust port 12 for purified air is protruded from the side of the cover case 8. The cover case 8 may be of an openable / closable type that rotates around one side of the cover case 8.

[0025] The main body case 7 of the air cleaner 5 is in the shape of a box that opens upward, with a rim 11b similar to that of the cover case 8 formed integrally with the outside of the opening edge, and the lower end of a clip 10 is engaged at the rim 11b. In addition, bracket parts 13 for fixing to the vehicle frame are formed integrally with the outer surface and inner corners of the main body case 7. The bracket parts 13 are fixed to the vehicle frame (not shown) by bolts 14 equipped with vibration-proof grommets.

[0026] As shown in Fig. 8, an inlet 15 is provided in one corner of the bottom surface of the main body case 7, while as shown in Fig. 6, the duct unit 6 is provided with a receiving plate 16 on which the main body case 7 is fixed, and a discharge port 17 communicating with the inlet 15 of the main body case 7 is formed in the receiving plate 16. The receiving plate 16 and the main body case 7 are fixed (joined) by welding such as vibration welding.

[0027] As shown in FIG. 8, downward welding ribs 18 are formed on the underside of the main case 7, surrounding the periphery and the inlet 15 and crossing in the front-to-back and left-to-right directions, while upward welding ribs 19 are also formed on the receiving plate 16 of the duct unit 6, corresponding to the downward welding ribs 18 of the main case 7.

[0028] However, in addition to the upward ribs 19 for welding, a group of auxiliary ribs 20 for reinforcement is also formed on the support plate 16 of the duct unit 6, and the upward ribs 19 for welding and the group of auxiliary ribs 20 form a lattice shape. In Fig. 6, the upward ribs 19 for welding are shown by hatching, but as can be seen from this figure, grooves are formed in the upward ribs 19 for welding.

[0029] Although not shown in Fig. 8, a groove is also formed in the downward rib 18 for welding of the main case 7 (the upward rib 19 for welding in Fig. 6 is shown wider than it actually is). Note that Fig. 7 only shows a part of the upward rib 19 for welding, and a part of the upward rib 19 for welding and all of the auxiliary rib 20 are omitted. Note that the shape of the rib for welding the backing plate 16 and the main case 7 can be changed in various ways.

[0030] (2) Duct unit 4 and 5, the duct unit 6 is made up of a pair of shell-shaped members, a left shell-shaped member 21 and a right shell-shaped member 22, and is formed hollow by stacking the two shell-shaped members 21 and 22 and joining them by vibration welding or the like, and is provided with an intake duct 23 and first and second resonators 24 and 25. Therefore, both shell-shaped members 21 and 22 are formed with a bulge that forms the intake duct 23 and a bulge that forms the resonators 24 and 25. The aforementioned support plate 16 is integrally molded on the upper end of the right shell-shaped member 22.

[0031] 5 and 7, the welded surfaces (superimposed surfaces) of both shell-like members 21 and 22 are shown by hatching (therefore, the hatching does not show a cross section). Grooves (not shown) are also formed on the welded surfaces of both shell-like members 21 and 22.

[0032] 1, 4 and 5, the intake duct 23 has a first vertically long portion 23a at the upper end of which the intake port 26 opens and through which air flows downward, a second vertically long portion 23b at the upper end of which the discharge port 17 described above opens and through which air flows upward, and a bottom portion 23c that is connected to the lower ends of both vertically long portions 23a and 23b and through which air flows horizontally. Therefore, the intake duct 23 has a substantially U-shaped shape in a side view. It extends in a continuous line. The resonators 24 and 25 are disposed in a space surrounded by the two vertically elongated portions 23a, 23b and the bottom portion 23c. A drain portion 27 for discharging water is provided so as to protrude downward from the corner portion where the first vertically elongated portion 23a and the bottom portion 23c are connected.

[0033] Since the upper end of the second vertically elongated portion 23b opens into the receiving plate 16, the second vertically elongated portion 23b is necessarily disposed below the air cleaner 5, but the air intake port 26 at the upper end of the first vertically elongated portion 23a is at approximately the same height as the upper end of the air cleaner 5. For example, as can be seen from Figure 2, the air intake port 26 opens in a substantially horizontal direction (sideways) toward the cover case 8 of the air cleaner 5 (the opening direction can be set arbitrarily).

[0034] Therefore, the upper half of the first vertically elongated portion 23a is disposed in front of the air cleaner 5, but since the resonators 24, 25 are disposed below the air cleaner 5, the lower half of the first vertically elongated portion 23a is bent so as to enter below the air cleaner 5. By taking such a consideration, the intake device 1 can be made compact.

[0035] The first vertical portion 23a is bent at a gentle angle, and the radius of curvature of the connecting portion between the first vertical portion 23a and the bottom portion 23c is also curved as large as possible. Furthermore, the connecting portion between the bottom portion 23c and the second vertical portion 23b is curved to bulge toward the outside of the vehicle body. Therefore, the intake duct 23 forms a U-shape as a whole, while the connecting portion is smoothly curved, the first vertical portion 23a is smoothly curved, and the second vertical portion 23b is curved to bulge toward the outside of the vehicle body. Due to this curved shape, the air flows smoothly inside the intake duct 23 with almost no resistance. Therefore, the intake resistance is significantly suppressed.

[0036] The first resonator 24 is disposed close to the first vertically elongated portion 23a, and its lower end communicates with the bottom portion 23c via a first communication passage 28. On the other hand, the second resonator 25 is accommodated in a recess formed by curving the second vertically elongated portion 23b outward, and its lower end communicates with the lower portion of the second vertically elongated portion 23b via a second communication passage 29. The first resonator 24 has a larger volume than the second resonator 25, but it is also possible to set the two to the same volume, or to set the second resonator 25 to a larger volume than the first resonator 24.

[0037] On the other hand, the second resonator 25 is accommodated in a recess formed by curving the second vertically elongated portion 23b outward. Therefore, the space created by curving the second vertically elongated portion 23b is effectively utilized to prevent the occurrence of dead space. The lower end of the second resonator 25 communicates with the lower portion of the second vertically elongated portion 23b via the second communication passage 29.

[0038] As can be seen from Figures 1 and 2, the resonators 24, 25 bulge on both the front and rear sides of the mating surfaces of the two shell-shaped members 21, 22, but the amount of bulging of the right shell-shaped member 22 is greater than the amount of bulging of the left shell-shaped member 21. In other words, the resonators 24, 25 bulge significantly toward the rear. Since the resonators 24, 25 can bulge significantly in the left-right direction, the necessary volume can be secured while effectively utilizing the space below the air cleaner 5. This is one of the major advantages of this embodiment.

[0039] As shown in Fig. 2, an air bleed port 30 is provided protruding downward from the rear lower end of the first resonator 24. As shown in Figs. 5 and 7, internal ribs 31 are formed inside the resonators 24 and 25, intersecting vertically and horizontally in a lattice shape when viewed from the side. The internal ribs 31 are provided mainly for reinforcement purposes.

[0040] As described above, the receiving plate 16 is integrally formed with the upper end of the right shell-shaped member 22 and protrudes on both the front and rear sides of the plate that constitutes the right shell-shaped member 22. As shown in, for example, FIGS. and second resonator 25 is disposed below the backing plate 16, and a group of backing plate support ribs 32 is integrally connected to the plate portion of the right shell-like member 22 and the backing plate 16. Therefore, the backing plate 16 is stably held on the right shell-like member 22, and as a result, the duct unit 6 has a robust structure as a whole. As described above, the resonators 24, 25 are disposed below the receiving plate 16, so that the air cleaner 8, the resonators 24, 25, and the bottom portion 23c of the intake duct 23 are disposed in an overlapping state in a plan view.

[0041] 2 to 4 (particularly FIG. 2), a horizontal intake duct rib 33 continuing to the first resonator 24 is integrally formed on the first vertically elongated portion 23a of the left shell-shaped member 21 and the first vertically elongated portion 23a of the right shell-shaped member 22, and the front and rear intake duct ribs 33 are joined to each other. Therefore, the first vertically elongated portion 23a and the first resonator 24 are integrated to increase the stability of the first vertically elongated portion 23a.

[0042] 6 and 7, the right shell-shaped member 22 is provided with a first side rib 34 connecting the first vertically elongated portion 23a and the backing plate 16, and a second side rib 35 connecting the second vertically elongated portion 23b and the backing plate 16. These side ribs 34, 35 also significantly improve the robustness of the intake duct 23.

[0043] (3) Summary This embodiment has the above-mentioned configuration, and the air flows downward through the intake duct 23, then changes direction to upward at the second vertical section 23b and flows into the main body case 7 of the air cleaner 5. However, since the intake duct 23 is approximately U-shaped, embracing the resonators 24, 25, the length can be increased while making effective use of the space.

[0044] And because intake duct 23 has bottom portion 23c, flow resistance is significantly reduced compared to the U-turn or serpentine shape of Patent Document 2. In particular, because second vertical portion 23b is curved so as to bulge on the side opposite to first vertical portion 23a, the upward direction change of the airflow is extremely smooth, and pressure loss can be significantly reduced.

[0045] And, because two resonators 24, 25 are connected to the long intake duct 23, the resonators 24, 25 can fully function, significantly improving the vibration and noise suppression effect.More specifically, because the resonators 24, 25 bulge in both the front and rear directions while hidden below the air cleaner 5, as described above, the necessary volume is secured by effectively utilizing the space below the air cleaner 5, and as a result, the air expansion action and shock absorption action are greatly improved, greatly improving the vibration and noise suppression effect.

[0046] In the one-box type light van shown in Figure 9, as mentioned above, the air cleaner is arranged in a space surrounded by the side members, flow and lower body of the vehicle body, and this space is narrow with a limited vertical width. However, in this embodiment, the resonators 24, 25 expand in the front-to-rear direction below the air cleaner 5 to ensure the necessary volume, so that the height of the intake device can be made as low as possible, and therefore the device can be applied to a light van while maintaining a high noise prevention effect.

[0047] In addition, because the air flows upward in the second vertically elongated portion 23b, even if sand or water is mixed in the air, the sand or water can be prevented or significantly suppressed from flowing into the main body case 7 of the air cleaner 5. This improves the durability of the filter element 9.

[0048] In terms of structure, the intake duct 23 and the resonators 24, 25 are formed by inflating the shell-shaped members 21, 22, which exert a rib effect and greatly increase the robustness of the duct unit 6. In addition, the duct unit 6 is joined to the main body case 7 of the air cleaner 5 via the support plate 16, so that the duct unit 6 and the air cleaner 5 are firmly fixed together. Therefore, there is no risk of the duct unit 6 falling off due to vibrations caused by the running of the automobile or vibrations of the engine 4.

[0049] Furthermore, the receiving plate 16 and the right shell-shaped member 22 are connected by a group of receiving plate support ribs 32, so that the duct unit 6 has a lightweight yet robust structure. In this case, the receiving plate 16 protrudes on both the left and right sides of the right shell-shaped member 22, and the receiving plate 16 and the right shell-shaped member 22 form a T shape when viewed from the front, so that the duct unit 6 is suspended and supported by the main body case 7 in a well-balanced manner.

[0050] In addition, the backing plate 16 and the right shell-like member 22 are uniformly connected from the front to the rear by the group of backing plate support ribs 32, so the duct unit 6 exhibits strong resistance to vibrations that are swayed in the front-to-rear direction. Therefore, even if a front-to-rear moment acts on the duct unit 6 when the car is traveling, the duct unit 6 can maintain high strength without swaying back and forth relative to the air cleaner 5.

[0051] Although the embodiment of the present invention has been described above, the present invention can be embodied in various other ways. For example, the number of resonators is not limited to two, but may be one or three or more. Also, in the embodiment, the air that has passed through the second vertically elongated portion enters the main body case from below, but it may enter the main body case from the side (i.e., the discharge port may be opened sideways). The main body case of the air cleaner can also be fixed to the receiving plate with fasteners such as screws.

[0052] It is also possible to form the backing plate in an inverted L shape, extending from the upper end of the shell-shaped member on only one side, and place the resonator below the backing plate (i.e., forming the resonator to bulge mainly on one of the pair of shell-shaped members). [Industrial Applicability]

[0053] The present invention can be embodied in an intake system for an engine, and therefore has industrial applicability. [Explanation of symbols]

[0054] 1. Intake system 4 Engine 5 Air cleaner 6 Duct unit 7 Main unit case 8 Cover Case 9 Filter Element 15 Air inlet of main body case 7 16 Support plate 17 Outlet 18 Welding Down Rib 19 Upward rib for welding 21 Left shell-shaped member 22 Right shell-shaped member 23 Intake duct 23a First vertical section 23b Second vertical section 23c bottom 24,25 Resonator 26 Air Intake 27 Drain section 28,29 Communication path 32 Support plate support rib

Claims

1. The vehicle is equipped with an air cleaner, an intake duct that takes in air into the air cleaner, and a resonator that is integrally provided with the intake duct via a communication passage, The intake duct has a first vertically elongated portion having an intake port at an upper end through which air flows downward, a second vertically elongated portion having an exhaust port at an upper end through which air flows upward, and a bottom portion connected to the lower ends of both vertically elongated portions, and a main body case constituting a dirty chamber of the air cleaner is integrally connected to the upper end of the second vertically elongated portion, the air cleaner is disposed so as to overlap an entire length of a bottom portion of the intake duct in a plan view, while the resonator is disposed only in a space surrounded by the both vertically elongated portions and the bottom portion of the intake duct, The air cleaner, the resonator, and the bottom of the intake duct are arranged at different heights in a state where they overlap in a plan view. Intake system for engines.

2. The intake duct is formed on the mating surface of two shell-shaped members that are overlapped and joined together, and the first vertical portion, the bottom portion, and the second vertical portion are continuous with each other, a substantially horizontal receiving plate having the discharge port of the second longitudinal portion opened therein is integrally provided on one of the two shell-shaped members, and a main body case of the air cleaner is fixed to the receiving plate; 2. An engine intake system according to claim 1.

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