Intake system

Abstract

An intake system (1) having an intake pipe (2), a throttle-valve unit (6) and a clean-air pipe (8), wherein the throttle-valve unit has a first end side (28), which adjoins an inlet (4) of the intake pipe, and wherein the intake-pipe inlet (4) and the first end side (28) have interacting first contours, which clearly define an attachment position of the throttle-valve unit (6) to the intake pipe (2), characterized in that the first contours enclose at least one positioning pin (18) of the intake pipe (2), the positioning pin extending, in a first bore (12) of the throttle-valve unit (6), through a plane which is parallel to the first end side (28) and contains the centre of gravity of the throttle-valve unit.

Description

[0001] The present invention relates to an intake system with an intake manifold and a throttle valve unit, as known from DE 10 2011 081 780 A1, and to a method for assembling an intake system.

[0002] In this known intake system, the intake manifold and the throttle body have complementary flanges that are bolted together during assembly of the intake system. The end of the throttle body facing away from the intake manifold is not shown; how a clean air pipe is to be attached to this end, if necessary, is not specified in DE 10 2011 081 780 A1.

[0003] From WO 2015 / 083690 A1, a throttle valve unit is known, which is connected by means of screws that are clamped between an intake manifold and a clean air pipe.

[0004] Furthermore, US patent 2,766,974 A discloses a throttle valve assembly that is attached to the intake manifold of the engine via flanges and bolted in place.

[0005] Gradually tightening the throttle valve unit to the intake manifold and then the clean air pipe to the throttle valve unit is time-consuming.

[0006] If the throttle body is short enough, the assembly of the intake system can be simplified and sped up by first fitting the throttle body onto the intake manifold, then fitting the intake duct onto the throttle body, and finally bolting the intake duct through the throttle body to the intake manifold. During the time between fitting the throttle body onto the intake manifold and bolting it in place, there is a possibility that the throttle body could fall off and be damaged. Especially with a short throttle body, the throttle plate can protrude from the unit and be damaged by the fall. In this case, the throttle body must be discarded and replaced with a different one.

[0007] Therefore, there is a high demand for manufacturing and assembly technology that can achieve high productivity while minimizing the risk of damaging components during installation.

[0008] To satisfy this need, an intake system as described below is proposed according to one aspect of the present invention. The intake system comprises an intake manifold, a throttle valve assembly, and a clean air pipe, wherein the throttle valve assembly has a first end face adjoining an intake manifold inlet and a second end face adjoining an outlet of the clean air pipe, and wherein the intake manifold inlet and the first end face have interacting first contours that uniquely define the mounting position of the throttle valve assembly on the intake manifold. The first contours comprise a flange of the intake manifold surrounding the intake manifold inlet, wherein a number of bores are arranged distributed in the flange around the intake manifold inlet, each bore being aligned with a through-bore in the throttle valve assembly and a through-bore in a flange around an outlet of the clean air pipe.Screws are guided through the through-holes, engaging either an internal thread in the holes or a nut positioned behind the holes. Second contours of the throttle valve assembly and the outlet of the clean air pipe uniquely define the mounting position of the clean air pipe on the throttle valve assembly (6). The first contours comprise at least an intake manifold-side section of a second bore in the throttle valve assembly and a pin of the intake manifold engaging in the intake manifold-side section. The second contours comprise a clean air pipe-side section of the second bore and a pin of the clean air pipe engaging in the clean air pipe-side section. At least one positioning pin is anchored to the flange of the intake manifold, extending in a first bore of the throttle valve assembly through a plane parallel to the first end face, which contains the center of gravity of the throttle valve assembly.

[0009] This positioning pin provides a secure hold for the throttle valve unit during the period between being placed on the intake manifold and being screwed in, even if the direction in which the throttle valve unit is placed on the intake manifold is horizontal or even slightly rising in the installation position of the intake system in a vehicle.

[0010] The flange is preferably part of the aforementioned first contours.

[0011] To further improve safety against falling off, the positioning pin can be long enough to extend over a second end face of the throttle body assembly, which, when the intake system is fully assembled, connects to an outlet of the clean air pipe, or even protrude beyond this second end face. This way, the positioning pin also provides protection against falling off even if the throttle body assembly is not directly in contact with the intake manifold inlet, for example, because the mounting direction is horizontal and the throttle body assembly is therefore not pressed against the intake manifold inlet by its own weight, or because a sealing ring, which remains undeformed when mounted, keeps them separated between the intake manifold inlet and the throttle body assembly.

[0012] According to one embodiment, a bore can be provided in the clean air pipe into which the end of the positioning pin, extending beyond the second end face, engages. In this way, the bore and the positioning pin can form part of the second contour.

[0013] According to one embodiment, the cross-section of the positioning pin is no larger than the cross-section of the first bore along its entire length. This allows the throttle valve assembly to be fitted without requiring force that would deform the positioning pin or the throttle valve assembly.

[0014] According to one embodiment, the cross-section of the positioning pin is dimensioned to provide frictional contact with an inner surface of the first bore of the throttle valve assembly. The friction helps to hold the throttle valve assembly securely to the intake manifold during the period between placing the throttle valve assembly onto the intake manifold and screwing the throttle valve assembly and the clean air pipe together.

[0015] According to one embodiment, the number of positioning pins and first bores is at least two each. Two positioning pins and the bores that receive them are sufficient to clearly define a position in which the throttle valve assembly can be placed on the intake manifold. This ensures that once the intake manifold is in place, the throttle valve assembly is also in the correct position and both can be attached to the intake manifold without further positional adjustment.

[0016] In particular, the bore of the clean air pipe mentioned above can be formed in this flange.

[0017] Using one of the second bores in the throttle valve unit, both the throttle valve unit and the clean air pipe can be positioned relative to the intake manifold.

[0018] According to one embodiment, the number of second bores, the number of pins of the intake manifold engaging in them, and the number of pins of the clean air pipe engaging in them are each at least two. These are sufficient to unambiguously define the mounting position of the clean air pipe on the throttle body.

[0019] Another aspect of the invention relates to a method for assembling an intake system, as described above and below, comprising the steps: Placing a first end face of the throttle assembly on an intake manifold inlet in a mounting position in which a positioning pin of the intake manifold extends in a first bore of the throttle assembly through a plane parallel to the first end face, which contains the center of gravity of the throttle assembly, and wherein a pin of the intake manifold in the mounting position extends into a second bore of an intake manifold-side section of the throttle assembly; placing an outlet with a surrounding flange of the clean air pipe on a second end face of the throttle assembly, such that a pin of the clean air pipe engages in the second bore on the second end face;Clamping the throttle valve assembly between the intake manifold and the clean air pipe by means of screws that pass through aligned through-holes in the flange of the clean air pipe and the throttle valve assembly and engage with an internal thread of holes in a flange surrounding the intake manifold inlet or with a nut placed behind the holes.

[0020] Screws can be used for clamping, in particular, which extend through aligned bores in the intake manifold and the clean air pipe, and preferably also in the throttle valve unit.

[0021] One of the bores in the intake pipe and the clean air pipe may each have an internal thread to provide support for the screw.

[0022] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying figures. These show: Fig. 1 parts of an intake system according to the invention, Fig. 2 the intake system according to the invention in the assembled state, and Fig. 3 a throttle valve unit which is fitted onto an intake manifold.

[0023] Fig. 1Figure 1 shows a perspective exploded view of the intake system 1. The intake system 1 comprises an intake manifold 2, a throttle valve assembly 6, and a clean air pipe 8. The intake manifold 2 has an intake manifold inlet 4. The intake manifold inlet 4 is surrounded by a flange 32. A sealing surface of the flange 32 facing the throttle valve assembly 6 is flush with a surface normal (not shown) which, in the installed position of the intake manifold 4 in a motor vehicle, is oriented substantially horizontally. Positioning pins 18 and two pins 16, which are shorter than the positioning pins 18, project from the flange 32 in the direction of the surface normal. Bores 20, preferably threaded bores, also oriented in the direction of the surface normal, are distributed in the flange 32 around the intake manifold inlet 4.

[0024] As in Fig. 1The throttle valve assembly 6, as shown, has a housing with a central passage in which a throttle valve is pivotably mounted. The housing has a first end face 28, which faces the flange 32 of the intake manifold 2, and a second end face 30, which faces the clean air pipe 8. A plane 0, running parallel to both end faces 28 and 30, contains the center of gravity of the throttle valve assembly 6. The distance between the end faces 28 and 30 is smaller than the diameter of the central passage extending from one end face 28 to the other 30, so that the throttle valve can project beyond the end faces 28 and 30 in an open position. A first bore 12, a second bore 10, and optionally a through bore 22 are distributed around the central passage in the housing of the throttle valve assembly 6 and extend in the direction of the surface normal.

[0025] The clean air pipe 8 has an outlet 36 at one end facing the throttle valve unit 6, surrounded by a flange 38. Two pins 14 are anchored to the flange 38. The pins 14 are mirror images of the pins 16.

[0026] When assembling the intake system, throttle valve unit 6 is first placed onto the intake manifold inlet 4 of the intake manifold 2. This is done as shown in Fig. 2As shown, the first two bores 12 of the throttle valve assembly 6 engage the positioning pins 18 of the intake manifold 2. The positioning pins 18 extend from the flange 32 over the entire length of the bores 12 and intersect plane 0. The cross-section of the positioning pins 18 is dimensioned such that they frictionally engage with the inner surfaces of the bores 12. To ensure a secure frictional engagement on the one hand, and to prevent excessive friction from unnecessarily hindering the installation of the throttle valve assembly 6 on the other, the positioning pins have a non-circular cross-section that contacts the inner surfaces of the bores 12 only at several points around their circumference, e.g., in the form of a polygon, cross, or star. The positioning pins 18 can also be made of a different, more easily deformable material than the flange 32 and the housing of the throttle valve assembly 6, e.g., plastic.The positioning pins 18 prevent the throttle valve assembly 6 from falling off the intake manifold 2 when the throttle valve assembly 6 is not yet screwed to the intake manifold 2, even if the surface normal along which the throttle valve assembly 6 is slid onto the positioning pins slopes slightly upwards towards the flange 32. In practice, the inclination of the surface normal to the horizontal can be up to 10°.

[0027] Two pins 16 of the intake manifold 2 are each received in a section on the intake manifold side of second bores 10. The pins 16 are too short to reach the end face 30 or even plane 0; a section of the second bores 10 on the clean air side is empty. The engagement of the pins 18, 16 of the flange 32 in the bores 12, 10 of the throttle valve assembly 6 uniquely determines its position on the intake manifold 2; in this position, the bores 20 of the flange 32 are aligned with the through-bores 22 of the throttle valve assembly 6.

[0028] A position in which the clean air tube 8 can be inserted onto the second end face 30 of the throttle valve assembly 6 is clearly defined by the requirement that the pins 14 of the clean air tube 8 must engage in the clean air tube-side sections of the second bores 10. In this position, the through-holes 24 in the flange 36 of the clean air tube 8 align with the through-holes 22 of the throttle valve assembly 6. To attach the clean air tube 8 to the intake manifold and clamp the throttle valve assembly 6 between the intake manifold 2 and the clean air tube 8, it is sufficient to insert screws 26 into the through-holes 24 and 22 and engage them with the internal threads of the bores 20 (or, if the bores 20 are not threaded, with a nut placed behind the bores 20).

[0029] Fig. 3Figure 1 shows the intake system 1 in its assembled state. The clean air pipe 8 and the throttle valve unit 6 are attached to the intake pipe 2 by means of the screws 26. As can be seen in the fully assembled position of the intake system 1, the positioning pin 18 protrudes from the first end face 28 of the throttle valve unit 6, specifically from the first bore 12. Reference sign

[0030] 1 Intake system 2 Intake manifold 4 Intake manifold inlet 6 Throttle body unit 8 Clean air pipe unit 10 Second bore 12 First bore 14 Pin 16 Pin 18 Positioning pin 20 Bore 22 Through bore 24 Through bore 26 Screw 28 First end face 30 Second end face 32 Flange 34 Bore 36 Outlet 38 Flange

Claims

1. Intake system (1) having a suction pipe (2), a butterfly valve unit (6) and a clean air tube (8), the butterfly unit having a first front (28) following a suction tube inlet (4) of the suction tube, and the suction tube (4) and the first front (28) having a coupling position of the throttle valve (6) have a clear initial contours at the suction tube (2), with the first contours comprising a flange (32) of the suction tube (2) surrounding the suction tube (4), where the flange (32) around the suction tube inlet (4) is divided into a number of holes (20), each with a through hole (22) drilling, the butterfly valve unit (32) and a through hole (24) in a flange (38) around an outlet (36) of the clean-air tube (8), so that screws (26) through the through holes (24, 22) interfere in an inner thread of the holes (20) or in a mother placed behind the holes (20), with second contours of the throttle The valve unit (6) and the outlet (36) of the clean air tube (8) shall clearly indicate the position of the clean air tube (8) at the throttle valve unit (6), the first contours shall at least provide one suction side section of a second hole (10) of the throttle valve unit (6) and a pin (16) of the grooved suction section (2) and the second contours include a straight-air section of the second bore (10) and a pin (14) of the clean-air tube (8) that penetrates the straight-air section of the tube (14), with at least one positioning pin (18) anchored to the flange (32) of the suction tube (2), which is inserted in a first bore (12) the throttle valve unit (6) extends to a plane parallel to the first front (28), containing the center of gravity of the throttle valve unit.

2. suction system according to claim 1, where the butterfly unit (8) has a second front (30), followed by an outlet of the clean-air tube (8) and the positioning pin (18) of the suction tube (2) extends at least to the second front (30) or to the second front (30).

3. Intake system according to claim 2, where the positioning pin (18) extends into a hole (34) of the clean air tube (8).

4. Intake system according to one of the previous requirements, where the cross-section of the positioning pin (18) over its entire length does not exceed the cross-section of the first bore (12).

5. Intake system according to one of the previous requirements, where the cross-section of the positioning pin (18) is measured in order to fit on a surface of the first hole (12) of the throttle valve unit (6) with a friction-resistant finish.

6. Intake system according to one of the previous requirements, where the number of positioning pins (18) and first holes (12) is at least two.

7. Method for assembling an suction system consisting of a suction tube (2), a throttle valve unit (6) and a clean air tube (8) with the steps - of a first front (28) of the throttle valve unit (6) on a suction tube (2) inlet (4) in a position where a positioning pin (18) of the suction tube (2) is placed (b) in a first hole (12), the throttle valve unit (6) extends through a plane parallel to the first front (28), containing the center of gravity of the throttle valve unit (6), and a pin (16) of the suction tube (2) in the mounting position is placed in a second hole (10), a suction tube side section of the throttle valve unit (6); - Place an outlet (36) with a surround flange (38) of the clean-air tube (8) on the second front of the throttle valve unit (6) so that a pin (14) of the clean-air tube (8) enters the second hole (10) on the second front; - insert the throttle valve unit (6) between the suction tube (2) and Clean air tube (8) by means of screws (26), which are guided by mutually fluid through holes (24, 22) in the flange (38) of the pure air tube (8) and the throttle unit (6) with an internal screw flange (32) of holes (20) in a flange surrounding the suction tube inlet (4) (32) or with a mother placed behind the holes (20).

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