JPH09189222A - Heat insulator structure in exhaust manifold for generating hot air of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the fitting of a heat insulator by forming a warm-up chamber to heat the sucked air into an air cleaner on an exhaust manifold when the heat insulator is fitted to the exhaust manifold. SOLUTION: A lid plate 6 is fitted to a recessed part 4 provided on an exhaust manifold to form the inside of the recessed part 4 into a warm-up chamber to heat the outside air to be sucked into an air cleaner, and in constituting a heat insulator 7 by two metallic plates 7a, 7b, a part of the heat insulator between the lid plate and a part around the recessed part is held by one metallic plate, and the part is held by the lid plate and a part around the recessed part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulator structure for covering an exhaust manifold of an internal combustion engine so as to prevent heat damage from the exhaust manifold.

[0002]

2. Description of the Related Art In general,
When this heat insulator is made of a single metal plate, not only the heat insulating effect is low, but also the sound insulating effect against the radiated sound is low, which causes noise to increase. The heat and sound insulation effects are enhanced by using double metal plates.

Conventionally, when the heat insulator is attached to the exhaust manifold so as to cover it, as described in, for example, Japanese Utility Model Laid-Open No. 62-87165 and Japanese Utility Model Publication No. 3-30576. Since a plurality of boss portions are integrally provided on the outer peripheral surface of the exhaust manifold and the heat insulator is fastened to each boss with a bolt, the shape of the exhaust manifold becomes complicated. However, there is a problem that not only the number of steps for manufacturing the exhaust manifold by casting increases, but also the number of steps required for attaching the heat insulator increases.

An object of the present invention is to solve this problem by forming a warm air chamber for heating intake air of an air cleaner in an exhaust manifold.

[0005]

In the internal combustion engine, the present inventor can warm the intake air to the internal combustion engine by utilizing the heat of the exhaust manifold to warm the air and introduce the warm air into the air cleaner. One of the warm air generators using this exhaust manifold is provided with a recess for warm air generation in the exhaust manifold, and the inside of this recess is covered with a bolt or the like so as to close the recess. Paying attention to the fact that there is a plate formed in the warm air chamber and configured to warm the atmospheric air drawn into the air cleaner in this warm air chamber,
By utilizing this, the present invention has been completed.

That is, according to the present invention, "the outer peripheral surface of the exhaust manifold is provided with a cover plate in a recess provided therein and a warm air chamber for warming the atmospheric air sucked into the air cleaner is provided inside thereof. A heat insulator, which is made of a stack of two metal plates so as to cover the exhaust manifold, is attached to the exhaust manifold so as to be sandwiched between the cover plate and a portion around the recess. The portion sandwiched between the plate and the peripheral portion of the recess is formed by a single metal plate obtained by cutting one of the two metal plates in the heat insulator. " Is.

[0007]

As described above, the exhaust manifold is provided with a recess, and the inside of the recess is formed as a warm air chamber with a cover plate attached by a bolt or the like so as to close the recess. By configuring the heat insulator so as to be sandwiched between the peripheral portion of the recess and the cover plate, it is possible to form a warm air chamber in the exhaust manifold by attaching the cover plate to the exhaust manifold,
A heat insulator can be attached to the exhaust manifold.

However, when the heat insulator is configured to be sandwiched between the peripheral portion of the recess and the lid plate in a state where two metal plates are stacked, the both sides of the heat insulator are Even if a gasket for sealing is used, it is not possible to completely seal the part between the two stacked metal plates, so when the internal combustion engine is splashed with water, this water will flow from between the two stacked metal plates into the warm air chamber. This may result in inhalation and soiling of the filter element in the air cleaner, malfunction of the internal combustion engine, and the like.

On the other hand, in the present invention, as described above, the portion of the heat insulator that is sandwiched between the cover plate and the peripheral portion of the recess is formed of the two metal plates of the heat insulator. By configuring one of the metal plates by cutting one of the metal plates, the portion of the heat insulator having one metal plate is sandwiched between the lid plate and the peripheral portion of the recess. Therefore, it is possible to reliably prevent the water splashed on the internal combustion engine from being sucked into the warm air chamber from between the two metal plates of the heat insulator.

Therefore, according to the present invention, the installation of the heat insulator to the exhaust manifold is extremely simple by utilizing the provision of the warm air chamber in the exhaust manifold under the condition that water is not sucked into the warm air chamber. Has the effect that can be.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 indicates a cast exhaust manifold for the internal combustion engine 2, and the exhaust manifold 1 includes a collecting pipe portion 1a extending in the direction of the cylinder row of the internal combustion engine 2 and the collecting pipe portion 1a.
To the respective cylinders of the internal combustion engine 2 and a branch pipe portion 1b, and an exhaust pipe 3 is connected to one end of the collecting pipe portion 1a.

Further, on the upper surface of the collecting pipe portion 1a in the exhaust manifold 1, a recess 4 formed in a rectangle along the longitudinal direction of the collecting pipe portion 1a in a plan view is provided, and the periphery of the recess 4 is covered with an exhaust manifold. 1 is provided so as to be surrounded by a side wall plate 5 that is integrally formed with 1. Reference numeral 6 indicates a lid plate made of a metal plate. By attaching the lid plate 6 to the upper surface of the side wall plate 5 in the recess 4 with a plurality of bolts 8, the inside of the recess 4 is It is formed in a warm air chamber for warming intake air to an air cleaner (not shown). That is, the lid plate 6 is provided with an inlet 6a for introducing atmospheric air and a warm air outlet 6b for the air cleaner so as to warm intake air to the air cleaner in the recess 4.

Reference numeral 7 indicates a heat insulator for covering substantially the entire exhaust manifold 1. The heat insulator 7 is formed by stacking two metal plates 7a and 7b and then stacking the two metal plates 7a. , 7b are spot-welded at a plurality of points. Then, the heat insulator 7 is formed with a hole 9 having the same shape as the recess 4 in a part thereof, and then the recess 4 is formed.
It is configured to be attached to the exhaust manifold 1 by being sandwiched between the upper surface of the side wall plate 5 and the lid plate 6.

In this case, the portion of the heat insulator 7 that is sandwiched between the upper surface of the side wall plate 5 in the recess 4 and the lid plate 6 has two metal plates 7a, Of the metal plates 7b, the metal plate 7b on the back side is cut off to constitute one metal plate 7a, and gaskets 10 and 11 for sealing are provided on both surfaces of this part
It is configured to be sandwiched between the lid plate 6 and the upper surface of the side wall plate 5 in the recess 4 to which the above is applied.

With this structure, by attaching the cover plate 6 to the exhaust manifold 1, a warm air chamber can be formed in the exhaust manifold 1, and the heat insulator 7 can be attached to the exhaust manifold 1. it can. In addition, a portion of the heat insulator 7 that is sandwiched between the upper surface of the side wall plate 5 in the recess 4 and the lid plate 6 is provided on the back side of the two metal plates 7 a and 7 b in the heat insulator 7. Since the metal plate 7b is cut off and configured by one metal plate 7a, the portion of the heat insulator 7 where the metal plate is one, the upper surface of the side wall plate 5 in the recess 4 and the lid plate 6 are formed.
Since it will be sandwiched between the two, the water splashed on the internal combustion engine is
It is possible to reliably prevent the air from being sucked into the recess 4, that is, the warm air chamber, from between a and 7b.

As shown in FIGS. 5 and 6, a single metal plate 7a in the portion of the heat insulator 7 which is sandwiched between the upper surface of the side wall plate 5 and the cover plate 6 in the recess 4 is provided. By providing the beads 7a 'so that the beads 7a' go around the entire circumference of the recess 4, the sealing performance can be further improved. Further, both gaskets 8 and 9 applied to both surfaces of one metal plate 7a in a portion of the heat insulator 7 which is sandwiched between the upper surface of the side wall plate 5 and the lid plate 6 in the recess 4, As shown in FIG. 6, with respect to the one metal plate 7a, at least two bolt holes 7a ″ out of the bolt holes 12 formed in the one metal plate 7a are attached to the fitting pieces 13. Since the heat insulator 7 can be incorporated together between the upper surface of the side wall plate 5 and the cover plate 6 in the recess 4 by fixing the same, there is an advantage that the mounting can be further simplified.

Furthermore, as described above, the portion of the heat insulator 7 that is sandwiched between the upper surface of the side wall plate 5 and the lid plate 6 in the recess 4 is divided into two parts in the heat insulator 7. Metal plates 7a, 7b
When the back metal plate 7b of the heat insulator 7 is formed of a single metal plate 7a, a portion of the heat insulator 7 that is sandwiched between the upper surface of the side wall plate 5 and the lid plate 6 in the recess 4. The external shape can be improved and the water splashed on the internal combustion engine can be improved as compared with the case where the one metal plate 7b is formed by cutting the front metal plate 7a of the two metal plates 7a and 7b. There is an advantage that it is possible to reduce the entry of the metal between the two metal plates 7a and 7b.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an exploded perspective view.

FIG. 5 is an enlarged sectional view taken along line VV of FIG. 4;

FIG. 6 is an enlarged sectional view taken along line VI-VI of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Exhaust manifold 2 Internal combustion engine 1a Exhaust manifold collecting pipe section 1b Exhaust manifold branch pipe section 4 Recess 5 Side wall plate 6 Lid plate 7 Heat insulator 7a, 7b Metal plate

Claims (1)

[Claims] 1. A warm air chamber for warming atmospheric air sucked into an air cleaner is provided on the outer peripheral surface of an exhaust manifold, the cover plate being installed in a recess provided therein, and the exhaust manifold is provided with a warm air chamber. A heat insulator made of two metal plates stacked so as to cover the exhaust manifold is attached so as to be sandwiched between the lid plate and a portion around the recess, and the lid plate and the recess of the heat insulator are attached. For generating warm air in an internal combustion engine, characterized in that the portion sandwiched between the peripheral portion of the heat insulator and one of the two metal plates of the heat insulator is formed by cutting one of the metal plates. Structure of the heat insulator in the exhaust manifold.