JP2012140892A - Intake manifold made of resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake manifold made of a resin, which can be integrated by subjecting resin parts to vibration welding even when arranging a branched pipe obliquely with respect to a vibration surface.SOLUTION: The intake manifold made of a resin includes a surge tank 10 which suppresses pulsation of intake air and a plurality of branched pipes 14a, 14b, 14c which introduce the intake air into a plurality of cylinders of an engine 12 from the surge tank 10, and is formed by subjecting the plurality of resin parts 40, 42, 44 to the vibration welding. Welding surfaces 43a, 43a', 43b, 43b', 43c, 43c', 48a, 48a', 48b, 48b', 48c, 48c' between the resin parts are set to connection parts where the branched pipes are connected to the surge tank. The welding surfaces are formed to be the same surface parallel to the vibration direction when adjacent parts of the branched pipes adjacent to each other are subjected to the vibration welding and to set both side parts of hole parts 46a, 46b, 46c of the respective branched pipes to be surfaces parallel to the vibration direction and different from one another.

Description

  The present invention relates to a resin intake manifold for supplying combustion air to an engine such as an automobile.

  Intake manifolds made of resin have been adopted instead of conventional light alloys such as aluminum alloys from the viewpoint of weight reduction and manufacturing cost reduction. The intake manifold has a surge tank that absorbs the pulsation of the air flow that flows in from the throttle body, a branch pipe that guides air to multiple cylinders of the engine, and a flange that is attached and fixed to the engine. Configured. A resin intake manifold is usually manufactured by molding a resin into several parts and vibration welding them together to integrate them. The smaller the number of parts, the less time is required for mold production, molding and welding, and the manufacturing cost can be reduced.

  The structure of resin intake manifolds tends to be complicated due to the fact that they are housed in a narrow space, etc., and the design becomes difficult due to the relationship between the moldability during mold forming and the vibration direction during vibration welding. Yes. In particular, the length of the branch pipes must be the same to prevent abnormal noise called rambling noise during intake, and depending on the arrangement, the position of the branch pipe opening to the surge tank is parallel to the joint surface of the parts. In some cases, the above-described problems are conspicuous.

  For example, in Patent Document 1, in the case of what is disclosed as the prior art in FIG. 4, the joint surface of two parts constituting the part of the branch pipe has a stepped shape, and the joint surface cannot be reciprocally vibrated. Therefore, it is said that it cannot be welded by the vibration welding method. Therefore, in the technique of FIG. 2 in the patent document, the hole is formed into a long hole shape in which two upper and lower arcs are connected by parallel straight portions, and all the straight portions are crossed by the joining surfaces of the two parts. I have to. Thereby, it is said that reciprocal vibration at the time of die-cutting and joining at the time of molding becomes possible.

JP 2006-161641 A

  However, in the prior art of FIG. 2 of Patent Document 1 described above, all adjacent straight portions are arranged so as to be aligned on one reference straight line including the vibration surface. A large slope cannot be applied. Therefore, the degree of freedom in designing the resin intake manifold is small, and it has been difficult to sufficiently cope with the problems described above.

  The present invention has been made in view of the above circumstances, and even when a plurality of branch pipes are arranged to be inclined with respect to the vibration surface, resin parts are molded, and these are vibration welded and integrated. It is an object of the present invention to provide a resin intake manifold which can be used.

  In order to achieve the object, the resin intake manifold according to claim 1 includes a surge tank that suppresses pulsation of intake air, and a plurality of branch pipes that introduce intake air from the surge tank to a plurality of cylinders of the engine. A resin intake manifold formed by vibration welding of a plurality of resin parts, wherein the plurality of branch pipes define respective inlets of the branch pipes at connection portions where the plurality of branch pipes are connected to the surge tank. The joint surfaces on both sides are formed so as to be parallel to the vibration direction at the time of vibration welding and different from each other on both sides, and the joint surfaces of the adjacent branch pipes are the same surface parallel to the vibration direction. It is characterized by that.

  In the first aspect of the present invention, even when a plurality of branch pipes are arranged to be inclined with respect to the vibration surface, the junction surfaces of adjacent branch pipes are made to be the same plane parallel to the vibration direction. Two resin parts forming the tube can be easily joined by vibration welding. Therefore, when the branch pipe is formed by vibration welding, the steps of the intake port can be stepped sequentially, so that the equalization of the plurality of branch pipes can be easily realized. Further, the branch pipe can be made equal in length by an easy method of arranging a plurality of intake ports with steps, so that the degree of freedom in design is greatly improved. In consideration of die cutting when molding individual parts, the shape of the hole that is the air inlet should be the widest at the joint surface. It can be a straight line or a tangent line.

  According to a second aspect of the present invention, there is provided the resin intake manifold according to the first aspect, wherein the branch pipe has two pairs of curved portions having different curvatures on the inlet opening surface that opens to the surge tank. It is characterized by.

  In the invention according to claim 2, by arranging the small curvature portions of the branch pipes adjacent to each other, it is possible to arrange the joining surface even if there is a step in the position of the branch pipe and to easily mold the parts. Can be set.

  The resin intake manifold according to claim 3 is the curved portion having a larger curvature in the intake port opening surface where the branch pipe opens into the surge tank in the invention according to claim 1 or 2. And a flange connected to the engine is formed at the tip thereof.

  In the third aspect of the present invention, the intake pipes that open to the surge tank are routed closer to the intake pipe closer to the flange, and the length of the branch pipe becomes shorter. However, by arranging the curved portion having a large curvature on the side where the flange is arranged, the intake port closer to the flange can take a higher height from the flange, and the length of the branch pipe close to the flange can be extended. Become. This makes it easier to lengthen the plurality of branch pipes. Therefore, the difference in distance between each branch pipe and the flange is reduced, and the step can be increased accordingly.

  According to the present invention, a plurality of branch pipes are arranged to be inclined with respect to a vibration surface in a resin intake manifold that is manufactured by molding resin parts and molding them by vibration welding. Therefore, even when the engine and the surge tank are arranged at a short distance, it is possible to achieve the equal length while sufficiently securing the length of the branch pipe. Further, it is possible to give a degree of freedom to the arrangement of the branch pipes, and it is possible to provide a product with high performance at a low cost.

It is a top view which shows the whole resin-made intake manifold which concerns on embodiment of this invention. It is the figure which fractured | ruptured the resin-made intake manifold of FIG. 1 along the II-II line. It is a perspective view which decomposes | disassembles into parts and shows the resin intake manifold of FIG. It is a side view which shows the 2nd component before welding with a 1st component. It is the schematic which shows the state which attached the resin-made intake manifold of FIG. 1 to the engine from the side.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing the entirety of a resin intake manifold according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II. The resin intake manifold includes a surge tank 10 that absorbs pulsation of air flowing from a throttle body (not shown), and branch pipes 14a and 14b for individually guiding air to a plurality of cylinders of an engine 12 (see FIG. 5). 14c and a flange 16 for attaching and fixing them to the engine 12. The resin intake manifold is manufactured by molding a resin into three parts 40, 42, and 44 as will be described later in this example, and vibration welding them together to integrate them.

  The surge tank 10 is a box-shaped member, which is provided with a flange mounting surface 17 for mounting a pipe for air flowing into one surface, and intake passages of three branch pipes 14a, 14b, 14c are opened on the other surface. (Suction port 13) is provided. At the other end of each of the three branch pipes 14a, 14b, 14c, a flange 16 for connecting to three cylinders (not shown) of the engine 12 is provided. The engine is located below the surge tank, and the arrangement direction of the three branch pipes 14a, 14b, 14c is twisted approximately 90 degrees on the inlet side and the outlet side, so the branch pipes 14a, 14b, 14c It has a twisted complex structure as shown. That is, as shown in FIG. 2, the arrangement of the inlets 13 on the inlet side of the plurality of branch pipes and the portions connected thereto is inclined so as to descend with increasing distance from the engine with respect to the horizontal plane. As shown by the line II-II, it is inclined with respect to a vertical plane including the traveling direction. Furthermore, as shown in FIG. 5, the surface of the engine 12 to which the flange 16 is attached is slightly inclined from the vertical surface, and the flange 16 surface is similarly inclined.

  The three branch pipes 14a, 14b, and 14c are substantially horizontal portions (horizontal portions) 18a, 18b, and 18c following the suction port 13, and portions that descend substantially vertically from the tips of the horizontal portions 18a, 18b, and 18c (vertical portions). Part) 20a, 20b, 20c, and parts (terminal parts) 22a, 22b, 22c connected to each cylinder from the lower ends of the vertical parts 20a, 20b, 20c. Is different. That is, in the first branch pipe 14a farthest from the engine 12, the vertical portion 20a is shortened, and the end portion 22a is made long and linear. On the other hand, the third branch pipe 14c close to the engine 12 has a longer vertical portion 20c and a curved end portion 22c. The positions of the inlets 13 and the horizontal portions 18a, 18b, 18c of the three branch pipes 14a, 14b, 14c are arranged in a direction inclined with respect to the plane orthogonal to the traveling direction. This is for facilitating the arrangement of 14a, 14b, and 14c. With such a configuration, a resin intake manifold is manufactured with a small number of molded parts while keeping the lengths of the branch pipes 14a, 14b, and 14c the same. be able to.

  The flange 16 is a plate-like member in which the outlets 24 of the branch pipes 14 a, 14 b, 14 c corresponding to the positions of the cylinders of the engine 12 are arranged at equal intervals in the longitudinal direction, and are bolt holes for fixing to the engine 12. 26 is formed at a predetermined location. A fuel injection valve fixing boss 30 for attaching the fuel injection valve 28 (see FIG. 5) to the outlet 24 at a predetermined angle is provided at a location corresponding to the outlet 24 of the branch pipes 14a, 14b, and 14c. Is formed. A rib member (not shown) is erected on the rear surface side (engine 12 side) of the flange 16, and the periphery of the bolt hole 26 and the fuel injection valve fixing boss 30 is also reinforced in a cylindrical shape. It comes to have a strong strength.

  This resin intake manifold is made of three resin parts 40, 42, and 44 as shown in FIG. The first component 40 includes a portion (upper side) that forms the horizontal portions 18a, 18b, and 18c of the surge tank 10 and the branch pipes 14a, 14b, and 14c, and the second component 42 includes the surge tank 10 and the branch. Partial portions (lower side) forming the horizontal portions 18a, 18b, 18c of the tubes 14a, 14b, 14c, vertical portions 20a, 20b, 20c of the branch tubes 14a, 14b, 14c, and end portions 22a, 22b, 22c The third part 44 includes a part (lower side) that forms the end portions 22a, 22b, and 22c of the branch pipes 14a, 14b, and 14c. Accordingly, the horizontal portions 18a, 18b, 18c of the surge tank 10 and the branch pipes 14a, 14b, 14c are formed by joining the first part 40 and the second part 42, and the branch pipes 14a, 14b, 14c. The end portions 22a, 22b, and 22c are formed by joining the second component 42 and the third component 44 together. The vertical portions 20 a, 20 b, 20 c of the branch pipes 14 a, 14 b, 14 c are formed by only one part of the second part 42. In this embodiment, these parts 40, 42, and 44 are produced by resin molding using a mold, vibrated along the joint surfaces in a state where the joint surfaces are abutted with each other, and welded by the frictional heat. . For this reason, the joint surface must be parallel to the vibration direction.

  As described above, the inlets 13 of the branch pipes 14a, 14b, 14c and the holes of the horizontal portions 18a, 18b, 18c connected thereto are arranged so as to be inclined with respect to the horizontal plane (see FIG. 2). Further, the holes 46a, 46b, and 46c, which are the intake passages of the horizontal portions 18a, 18b, and 18c of the branch pipes 14a, 14b, and 14c, have a flat cross-sectional shape instead of a circular shape. In this example, the cross-sectional shapes of the holes 46a, 46b, and 46c are slightly elongated rectangles, and are arranged so that each side (straight line portion) is substantially horizontal and vertical. The corner portion 19 (curved portion) is set so that the curvature of the pair of corner portions 19a along the inclination direction is small and the curvature of the other pair of corner portions 19b is large. As a result, among the plurality of intake ports that open to the surge tank, the intake port closer to the flange can be arranged at a higher (separated) position relative to the flange position. It can be placed at a low (close) position relative to the position. Therefore, the branch pipe of the intake port close to the flange among the plurality of intake ports that open to the surge tank tends to be routed and the pipe length of the branch pipe tends to be shortened, but the intake port closer to the flange tends to be higher from the flange position. The distance (distance) can be increased, and the height (distance) from the flange position can be reduced as the intake port is farther from the flange. Therefore, the length of the branch pipe close to the flange can be extended, and the length of the branch pipe close to the flange can be shortened. . Thereby, since the pipe lengths of the plurality of branch pipes can be adjusted, it is possible to make the lengths easier. At least a part of the vertical walls of the holes 46a, 46b, 46c of the branch pipes 14a, 14b, 14c overlap each other in the vertical direction. Therefore, by arranging the joining surfaces 48a, 48a ′, 48b, 48b ′, 48c, 48c ′ here, the die-cutting of both parts 40, 42 can be performed at the time of molding by joining surfaces 48a, 48a ′, 48b, 48b ′, It is possible to perform in a direction orthogonal to 48c and 48c ′. Since the six joint surfaces 48a, 48a ', 48b, 48b', 48c, 48c 'formed on both sides of each branch pipe 14a, 14b, 14c are all formed along the vibration direction, vibration welding is possible. Needless to say.

  In the cross section shown in FIG. 2, the joining (boundary) surfaces of the first part 40 and the second part 42 are provided with holes 46 a, 46 b, in order to define respective intake passages of the branch pipes 14 a, 14 b, 14 c. 46c is provided at each of the positions on both sides. The first part 40 and the second part 42 have their inlets 13 formed by joining their joint surfaces by vibration welding, and FIG. 2 shows a state where they are joined by vibration welding. FIG. Therefore, the welding surface (bonding surface) is in a state of being chipped by vibration welding. FIG. 4 shows the joint surface of the second component 42 before vibration welding. As can be seen from FIG. 2 and FIG. 4, 48a and 48a ′ which are the joint surfaces of the hole 46a, 48b and 48b ′ which are the joint surfaces of the hole 46b, and 48c and 48c ′ which are the joint surfaces of the hole 46c, respectively. Is formed. Corresponding to these six joint surfaces of the second component 42, the first component 40 is formed with six joint surfaces 43a, 43a ′, 43b, 43b ′, 43c, 43c ′. Has been. These planes are parallel to the plane including the vibration direction during vibration welding. In this example, as shown in FIG. 1, the vibration direction is the front-rear direction of the vehicle, and each is indicated by a bidirectional arrow in FIGS. 1 and 2. As shown in FIG. 4, the joint surfaces 48a, 48a ′, 48b, 48b ′, 48c, and 48c ′ of the second component 42 are formed in a convex shape, and a gap 54 is formed in the vibration direction between the convex shapes. Vibration is allowed.

  In the resin intake manifold of the embodiment of the present invention configured as described above, the joint surfaces 48a between the parts 40, 42 at the connection portion where the plurality of branch pipes 14a, 14b, 14c are connected to the surge tank 10, 48a ′, 48b, 48b ′, 48c, 48c ′ (joint surfaces in the second part 42) are adjacent joint surfaces (joint surfaces 48a ′, 48b, and 48b) of the adjacent branch pipes 14a, 14b, 14c. ′ And the joint surface 48c) are made to be the same plane parallel to the vibration direction at the time of vibration welding, and the portions on both sides of the holes 46a, 46b, 46c of the branch pipes 14a, 14b, 14c are parallel to the vibration direction and different from each other. It is formed to be a surface. In this embodiment, the joint surface 48a ′ and the joint surface 48b, which are two adjacent joint surfaces, are the same surface, and the joint surface 48b ′ and the joint surface 48c, which are two adjacent joint surfaces, are configured as the same surface. Yes. Furthermore, the joint surfaces on both sides that define the intake port positions (heights) of the joint surfaces that divide the intake port 13 so that the joint surfaces (48a ′, 48b) and the joint surfaces (48b ′, 48c) are different surfaces. It is changed and arranged. Therefore, the joining surface 48a and the joining surfaces (48a ', 48b) are also arranged on different surfaces, and the joining surface (48b', 48c) and the joining surface 48c 'are also arranged on different surfaces. As described above, since the joint surfaces 48a, (48a 'and 48b), (48b' and 48c), and 48c 'are arranged on different surfaces in parallel to the vibration direction, as shown in FIG. Arranged. As a result, even if there are steps at the positions of the branch pipes 14a, 14b, and 14c, the joint surfaces 48a, 48a ′, 48b, 48b ′, 48c, and 48c ′ have steps other than the gap 54 for allowing vibration. And can be easily and firmly joined by vibration welding. Therefore, it is possible to provide a resin-made intake manifold with good performance without increasing the manufacturing cost.

  Further, in this embodiment, since the opening surface of the inlet port 13 opened to the surge tank 10 of the branch pipes 14a, 14b, and 14c is formed to have two pairs of curved portions having different curvatures, the overall smoothness is achieved. As described above, the adjacent joint surfaces (48a ′ and 48b) and the adjacent joint surfaces (48b ′ and 48c) can be easily secured on the same surface while maintaining a simple shape. Further, since the branch pipes 14a, 14b, 14c are bent toward the curved portion having a larger curvature and a flange is formed at the tip thereof, the distance between each branch pipe 14a, 14b, 14c and the flange 16 is short. Even when the handling of the branch pipes is restricted, the pipe length of the branch pipes can be made as long as possible, and the plurality of branch pipes can be made equal in length. In this embodiment, since the branch pipe 14c is disposed at a position closest to the flange, normally, when the branch pipe is routed from the surge tank, the pipe length is shorter than other branch pipes. Conversely, the branch pipe 14a farthest from the flange has the longest pipe length. However, the position (height) of the intake port opening in the surge tank is changed, the intake port 13c of the branch pipe 14c is arranged at the highest position farthest from the flange, and the intake port 13a of the branch pipe 14a is the lowest closest to the flange. By arranging in the position, the lengths of the plurality of branch pipes are adjusted to make the branch pipes equal in length. In order to prevent abnormal noise such as rambling noise, it is necessary to align the length of multiple branch pipes. However, if the flange and surge tank are close to each other, multiple branch pipes must be stacked. This increases the number of divisions and a complicated manufacturing method, which increases costs. However, in the present embodiment, since the length is made equal by changing the opening position of the intake port of the surge tank, it can be manufactured without increasing the number of divisions or a complicated manufacturing method.

  The cross-sectional shapes of the holes 46a, 46b, 46c of the branch pipes 14a, 14b, 14c, for example, the aspect ratio and the curvature of the corners are the same in cross-sectional area and air resistance, etc. As long as the joint surfaces 48a, 48a ′, 48b, 48b ′, 48c, and 48c ′ can be set while maintaining the mold release property, the branch pipes 14a, 14b, and 14c can be appropriately set. For example, a simple rectangle may be used, or a polygon having the maximum width at the position of the joint surfaces 448a, 48a ', 48b, 48b', 48c, 48c'8 may be used. Since the joining surface may be formed along the vibration direction, it may be a curved surface such as a cylindrical surface. In this example, the vibration direction is horizontal, but may be set obliquely in consideration of other parts.

10 Surge tank 12 Engine 14a, 14b, 14c Branch pipes 43a, 43a ′, 43b, 43b ′, 43c, 43c ′ Joint surfaces 48a, 48a ′, 48b, 48b ′, 48c, 48c ′ Joint surfaces

Claims (3)

A resin intake manifold that includes a surge tank that suppresses pulsation of intake air and a plurality of branch pipes that introduce intake air from the surge tank to a plurality of cylinders of an engine, and is formed by vibration welding of a plurality of resin parts. And
In the connection portion where the plurality of branch pipes are connected to the surge tank, both side joint surfaces that define the respective intake ports of the branch pipes are parallel to the vibration direction at the time of vibration welding and are different from each other on both sides. The joint surface of the resin intake manifold is characterized in that the joint surfaces of adjacent branch pipes are the same surface parallel to the vibration direction.   2. The resin intake manifold according to claim 1, wherein the branch pipe has two pairs of curved portions having different curvatures on the inlet opening surface that opens to the surge tank.   The branch pipe is bent toward the curved portion having a larger curvature at the inlet opening surface opened to the surge tank, and a flange connected to the engine is formed at the tip of the branch pipe. The resin intake manifold according to claim 1 or 2.

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