JPH0628256U - Intake duct - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an air intake duct which has a side branch, which does not look bad, and which has a durable mounting portion for the side branch and has a good sealing property. [Structure] A side branch 2 formed of a hollow body extending along the longitudinal direction of the intake duct 1 on an outer wall of an appropriate place of the intake duct 1.
A connecting tube in which a communication hole 3 is formed in a portion of the outer wall of the intake duct 1 facing the one end of the side branch 2 and a packing 4 is attached to the inner periphery of the communication hole 3 and which is projected from one end of the side branch 2. 5 was press-fitted into the communication hole 3, and both ends of the side branch 2 were screwed to the outer wall of the intake duct 1 with tapping screws 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an intake duct for an internal combustion engine, and more particularly to an intake duct equipped with a side branch for noise reduction.

[0002]

[Prior art]

 It has been conventionally known that a silencing effect can be obtained by connecting a side branch made of a hollow body at a proper position in an intake duct of an internal combustion engine. As such a side branch, as shown in FIGS. 4 and 5, a side branch 12 formed of a bent pipe having a closed distal end and a joint opening 13 formed at the proximal end is formed at an appropriate position of the intake duct 11. It is known that the tube mouth 14 is fitted and the fitting joint surface is adhered with a butyl rubber adhesive 15.

In Japanese Utility Model Laid-Open No. 2-63067, as shown in FIG. 6, a recess 22 is formed at an appropriate position on the bottom surface of an intake duct 21, and a silencer box 23 is housed and mounted therein. The silencer box 23 and the inside of the intake duct 21 are disclosed by a communication hole 24.

[0004]

[Problems to be solved by the device]

 However, in the configuration shown in FIGS. 4 and 5, there is a problem in that the side branch 12 does not look good because it projects long in the perspective direction with respect to the intake duct 11, and due to the vibration of the side branch 12, the side branch 12 has a problem. Since a large repetitive stress acts on the joint surface between the joint port portion 13 and the connecting cylinder port 14 of the intake duct 11, there is a problem in the durability of the joint portion, and since the butyl rubber adhesive 15 adheres, the sealing property is high. There is also the problem of being bad.

Further, in the configuration shown in FIG. 6, the silencer box 23 does not project from the intake duct 21 at all, so that the appearance is good, but the intake duct 21 has a recess 22 for accommodating the silencer box 23. Therefore, there is a problem that the flow passage cross-sectional area is narrowed at that portion, and the air flow is disturbed, and the noise reduction effect is also reduced. Furthermore, the length of the intake duct 21 varies depending on the model of the internal combustion engine. As a result, there is a problem in that it is necessary to manufacture different air intake ducts for each model when the position of the silencer box 23 is different.

In view of such conventional problems, the present invention provides an air intake duct that includes a side branch, does not look bad, and has a side branch mounting portion that is durable and has a good sealing property. With the goal.

[0007]

[Means for Solving the Problems]

 According to the present invention, a side branch consisting of a hollow body extending along the longitudinal direction of the intake duct is arranged on the outer wall of the intake duct at a proper position, and a communication hole is formed at a portion of the outer wall of the intake duct facing one end of the side branch. It is characterized in that a packing is attached to the inner periphery thereof, a connecting cylinder protruding from one end of the side branch is press-fitted into the communication hole, and both ends of the side branch are screwed to the outer wall of the intake duct.

[0008]

[Action]

 According to the present invention, the side branch is arranged along the outer wall of the intake duct, does not significantly project from the intake duct, does not look bad, and is less likely to cause vibration, and both ends of the side branch are screwed to the intake duct. Since it is installed, it is durable in its installed state.In addition, a connecting tube protruding from the side branch is fitted into the communication hole formed on the outer wall of the intake duct, and packing is interposed between them, resulting in a high seal. Sex is secured over the long term.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS.

Reference numeral 1 is an intake duct, and a communication hole 3 for connecting the side branch 2 is formed in an outer wall of the intake duct at an appropriate place. A packing 4 having a substantially U-shaped cross section is attached to the inner peripheral edge of the communication hole 3.

The side branch 2 is composed of a hollow body extending along the longitudinal direction of the intake duct 1, and a connecting cylinder 5 that can be inserted and fitted into the communication hole 3 is provided on a surface of one end of the side branch 2 facing the outer wall of the intake duct. Has been done.

A projecting piece 6 is projected from both ends of the side branch 2 so as to overlap with the outer wall of the intake duct 1. The projecting piece 6 is screwed to the outer wall of the intake duct 1 by a tapping screw 7. There is.

In the above-described structure, when the side branch 2 is mounted on the intake duct 1, the communication hole 3 is formed at a predetermined position of the intake duct 1 at the same time as another machining process. At this time, if the length of the intake duct differs depending on the model of the internal combustion engine and the arrangement position of the side branch 2 accordingly changes, the drilling position of the communication hole 3 may be adjusted. Next, at the time of assembling the side branch 2, the packing 4 is mounted on the inner peripheral portion of the mounting hole 3, and the connecting cylinder 5 of the side branch 2 is press-fitted into the communication hole 3 while compressing the packing 4. Is connected to the intake duct 1, and finally the projecting piece 6 is screwed to the intake duct 1 with a tapping screw 7 to complete the attachment of the side branch 2.

In the mounted state of the side branch 2, since the side branch 2 is arranged along the outer wall of the intake duct 1, the side branch 2 does not significantly project from the intake duct 1 and the side branch 2 is not good-looking. It never happens. Further, since the side branch 2 is arranged along the intake duct 1, vibration is unlikely to occur, and since both ends of the side branch 2 are screwed to the intake duct 1, the mounting state is durable. Further, since the connecting cylinder 5 of the side branch 2 is fitted into the communication hole 3 of the intake duct 1 via the packing 4, high sealing performance is ensured for a long period of time.

[0015]

[Effect of device]

 According to the air intake duct of the present invention, since the side branch is arranged along the outer wall of the air intake duct as described above, and does not significantly project from the air intake duct, the appearance is not bad and the side branch is not easily generated. Since both ends of the intake duct are screwed to the intake duct, it is durable in the installed state.In addition, a connecting tube protruding from the side branch is fitted into the communication hole formed in the outer wall of the intake duct, and packing is provided between them. Since it is installed, high sealing performance is ensured for a long time.In addition, there are different types of intake ducts with different lengths depending on the internal combustion engine model, but it is easy to adjust the machining position of the communication hole according to the type. The side branch can be placed at any position, which is effective.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of an embodiment of an air intake duct of the present invention.

FIG. 2 is a plan view of FIG.

3 is an enlarged cross-sectional view of a main part taken along the line AA of FIG.

FIG. 4 is a perspective view of a main part of a conventional intake duct.

5 is a cross-sectional plan view of the main part of FIG.

FIG. 6 is a front view of a main part of another conventional intake duct.

[Explanation of symbols]

 1 Intake duct 2 Side branch 3 Communication hole 4 Packing 5 Connection tube 7 Tapping screw

Claims (1)

[Scope of utility model registration request] 1. A side branch formed of a hollow body extending along the longitudinal direction of the intake duct is disposed on an outer wall of a proper place of the intake duct, and a communication hole is formed in a portion of the outer wall of the intake duct facing one end of the side branch. Intake duct characterized in that a packing is attached to the inner periphery of the side branch, a connecting cylinder protruding from one end of the side branch is press-fitted into the communication hole, and both ends of the side branch are screwed to the outer wall of the intake duct. .