JP2001115853A - Supporting device for heat shielding plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of chattering noise regardless of vibration propagating during operation, to facilitate manufacture of part items, control of a part, and assembly work, and to reduce a cost. SOLUTION: A sleeve 3 for insertion of a coupling member such as a bolt into a mounting hole 2 formed in a heat shielding plate 1 is supported through a buffering unit 8. The buffering unit 8 consists of a pair of buffering elements 4c and 4c formed in the same shape. Protrusion parts 10 and 10 formed on the buffering elements 4a and 4c are pressed in an annular gap 13 between the inner peripheral edge of the mounting hole 2 and the outer peripheral surface of the intermediate part of the sleeve 3 to prevent the outer peripheral surface of the sleeve 3 from abutting on the inner peripheral edge of the mounting hole 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a structure of a portion for supporting a heat shield, such as an exhaust manifold or a turbocharger, which is installed so as to cover a portion that becomes hot during operation. It is intended to prevent generation of harsh noise due to vibration transmitted during driving.

[0002]

2. Description of the Related Art In order to guide the exhaust of an automobile engine, the temperature of an exhaust manifold having an upstream end connected to the side of a cylinder head of the engine is considerably increased by the heat of the exhaust gas flowing inside. In order to protect other equipment provided in the engine room from the radiant heat radiated from the exhaust manifold whose temperature has risen in this way, the above exhaust manifold is covered with a heat shield plate called a heat insulator, and the exhaust manifold from the exhaust manifold. The radiant heat is prevented from being transmitted to the other devices. The same applies to turbochargers for supercharging the engine.

FIG. 2 shows an example of such a heat shield plate 1. The heat shield plate 1 can cover the exhaust manifold with a slight gap therebetween by pressing a single plate of a steel plate or a composite plate in which a sound absorbing material is sandwiched between aluminum-plated steel plates. It is formed in various shapes and sizes. Such a heat shield plate 1 has bolts inserted through circular mounting holes 2, 2 provided at a plurality of locations,
The connecting member such as a stud is supported and fixed to a mounting portion such as a mounting seat provided on the exhaust manifold.

The exhaust manifold emits a sound coming out of the engine during operation of the engine. Therefore, the heat shield plate 1 vibrates based on the radiated sound to prevent generation of harsh noise. A cushioning material is provided between the hot plate 1 and the coupling member. FIG. 3 shows a first example of a conventional structure of a heat-shielding plate support device for supporting and fixing the heat-shielding plate 1 to the mounting portion. In the structure of this first example, a cylindrical sleeve 3 is inserted into the inside of each circular mounting hole 2 formed at a plurality of locations on the heat shield plate 1. A pair of buffer elements 4 constituting a buffer unit are disposed around the mounting hole 2 so as to sandwich the heat shield plate 1 from both front and back sides. Each of the cushioning elements 4 and 4 is formed in a ring shape with a rectangular cross section by further press-molding a material formed by braiding a filament made of an elastic heat-resistant material such as stainless steel.
Further, washers 5, 5 each having an L-shaped cross section and a ring shape as a whole are superimposed on the outer end faces of the both buffer elements 4, 4 (the side faces opposite to the heat shield plate 1). In the case of the first example of the conventional structure shown in FIG.
Is larger than the inner diameter of the mounting hole 2, and the inner diameter of each of the washers 5, 5 is smaller than the inner diameter of the mounting hole 2.

[0005] In order to support and fix the heat shield plate 1 to the mounting portion by the heat shield plate support device of the first example of the conventional structure, which is formed by combining the above members, bolts, studs and the like are used. , A coupling member (not shown) is inserted through the sleeve 3,
This connecting member is screwed into a screw hole (when the connecting member is a bolt) or a nut (when the connecting member is a stud whose base end is fixed to the mounting portion) formed in the mounting portion. I will be even more tight. In this state, the sleeve 3
It is strongly clamped between the outer end surface of the mounting portion and the head or nut of the bolt, and is fixed to the mounting portion. At the same time, the buffer elements 4 are elastically compressed between the front and back surfaces of the heat shield plate 1 and the washers 5, respectively. Supported by

FIG. 4 shows a second example of a conventional structure of a heat shield plate supporting device for supporting and fixing the heat shield plate 1 to a mounting portion. In the structure of the second example, a pair of buffer elements 4a and 4b having different shapes are arranged around a cylindrical sleeve 3 inserted into the inside of the mounting hole 2 formed in the heat shield plate 1. Make up the unit. As in the case of the first example described above, one of the two buffer elements 4a and 4b (upper in FIG. 4) formed by further pressing and molding a material formed by braiding a filament made of a heat resistant material having elasticity. Buffer element 4
“a” is a mere cross-sectional rectangle and is formed in an annular shape as a whole.
On the other hand, the other (lower in FIG. 4) buffer element 4b includes a large-diameter portion 6 and a small-diameter portion 7, has a substantially L-shaped cross section, and is formed into a short cylindrical shape as a whole. I have. Then, in a state where the one buffer element 4a is externally fitted to the small diameter section 7 of the other buffer element 4b, one heat shield plate 1 is interposed between the one buffer element 4a and the large diameter section 6. The mounting hole 2
Is sandwiched.

In order to support and fix the heat shield plate 1 to the mounting portion by using the heat shield plate support device of the second example of the conventional structure, which is formed by combining the above members, bolts, studs and the like are used. The connecting member (not shown) is connected to the other buffer member 4b.
The coupling member is screwed into a screw hole or a nut formed in the mounting portion, and further tightened. In this state, the sleeve 3 is fixed to the mounting portion, and at the same time, the respective buffer elements 4a, 4b
However, the heat shield plate 1 is elastically compressed between the front and back surfaces of the heat shield plate 1 and the heads or nuts of the bolts, so that the heat shield plate 1 is supported by the mounting portion in a buffered manner.

[0008]

In the case of the first example of the conventional structure shown in FIG. 3, the inner peripheral edge of the mounting hole 2 and the outer peripheral surface of the intermediate portion of the sleeve 3 do not intervene through the cushioning material 4. They are directly opposed. Therefore, the heat shield plate 1 is displaced in the diametrical direction of the sleeve 3 due to the vibration generated with the operation of the engine, and the outer peripheral surface of the intermediate portion of the sleeve 3 can contact the inner peripheral edge of the mounting hole 2. There is. When vibration is applied while the outer peripheral surface of the intermediate portion of the sleeve 3 and the inner peripheral edge of the mounting hole 2 formed in the heat shield plate 1 are in contact with each other, which is a rigid body made of metal, chatter noise is generated at the contact portion. It is not preferable because it may cause discomfort to the occupants and those around them.

In the case of the second example of the conventional structure shown in FIG. 4, a small diameter portion 7 of the other cushioning material 4b exists between the inner peripheral edge of the mounting hole 2 and the outer peripheral surface of the intermediate portion of the sleeve 3. For this reason, the occurrence of chattering sound as described above can be prevented, but the cost increases and it is difficult to obtain stable performance. That is, the second
In the case of the example structure, since two types of cushioning materials 4a and 4b are used, manufacturing and parts management become troublesome, which causes an increase in cost. In addition, it is difficult to insert the small-diameter portion 7 of the other cushioning member 4b, which is soft and easily deformed, into the inner diameter side of the one cushioning member 4a, thereby deteriorating the efficiency of the assembling operation and also increasing the cost. . Furthermore, it is difficult to make the density of the small diameter portion 7 long in the axial direction (vertical direction in FIG. 4) and small in the thickness direction in the diametric direction uniform and to a desired value, and the shape retention of the small diameter portion 7 is poor. It is difficult to exhibit the desired performance because it is easy to be formed. The heat shield supporting device of the present invention has been invented in order to solve any of the above-mentioned disadvantages.

[0010]

The support device for a heat shield according to the present invention has the same structure as that of the above-described support device for a heat shield, which has a circular mounting hole formed in the heat shield. A cylindrical sleeve is supported via an elastic buffer unit, and the heat shield plate is buffer-supported on the mounting portion by a coupling member inserted through the sleeve. In particular, in the support device for a heat shield plate of the present invention, the buffer unit is formed by combining a pair of buffer elements each having an annular shape and the same shape, symmetrically arranged in the axial direction. It is. In addition, each of the buffer elements has a convex portion whose height dimension is smaller than the thickness dimension of the heat shield plate and which can enter the inside of the mounting hole, on the inner peripheral edge portion of the surfaces facing each other. Things. The respective buffer elements are inserted into the annular gap between the inner peripheral edge of the mounting hole and the outer peripheral surface of the intermediate portion of the sleeve from the openings at both ends of the mounting hole. Is composed.

[0011]

According to the heat shield plate supporting device of the present invention having the above-described structure, the buffer unit is formed between the inner peripheral edge of the mounting hole formed in the heat shield plate and the outer peripheral surface of the intermediate portion of the sleeve. Since the protrusions provided on the pair of buffer elements are present, the inner peripheral edge of the mounting hole and the outer peripheral surface of the intermediate portion of the sleeve are prevented from directly contacting each other, and chattering noise can be reliably prevented.
Further, since each of the buffer elements has the same shape, cost can be reduced by simplifying manufacturing and component management. In addition, each of the above-mentioned cushioning elements is long in the axial direction,
In addition, since there is no portion having a small thickness dimension in the diameter direction, the operation of uniformly processing the density of each of the buffer elements to a desired value can be easily performed. Furthermore, at the time of assembling, the projecting portion having a small axial dimension may be inserted into the annular gap between the inner peripheral edge of the mounting hole and the outer peripheral surface of the intermediate portion of the sleeve. The cost can be reduced by improving the efficiency.

[0012]

FIG. 1 shows a first embodiment of the present invention.
An example is shown. Inside a circular mounting hole 2 formed in the heat shield plate 1, a cylindrical sleeve 3 made of metal such as steel or stainless steel is supported via a buffer unit 8 made of a heat-resistant material having elasticity. And this sleeve 3 was inserted,
The heat shield plate 1 is buffer-supported by a connecting member (not shown) such as a bolt or a stud on a mounting portion, such as an exhaust manifold, provided at a portion which becomes hot during operation.
The buffer unit 8 is sandwiched from both sides in the axial direction (vertical direction in FIG. 1) by washers 5, 5 each having an L-shaped cross section and a ring shape as a whole. The inner diameter of the cylindrical portion 12 formed on the inner peripheral edge of the both washers 5, 5 is set to a size that can be fitted to the sleeve 3 without rattling, and the outer diameter is also smaller than the inner diameter of the mounting hole 2. ing.

The buffer unit 8 is formed by combining a pair of buffer elements 4c, 4c each having an annular shape and the same shape in a state where they are arranged symmetrically with respect to the axial direction (vertical direction in FIG. 1). Each of the buffer elements 4c and 4c has an annular convex portion 10 on the surface facing each other and an annular concave portion 11 on the opposite surface of the inner peripheral edge of the main portion 9 having a rectangular cross section. Consisting of Convex part 1 of these
Height H ₁₀ in the free state of 0, the barrier smaller than the thickness T ₁ of the hot plate 1, preferably more than half of the thickness _{T 1 (T 1/2 ≦} H 10 <T 1 ). However,
If the projection 10 is surely inserted into the mounting hole 2, the height H ₁₀ in the free state of the projection ₁₀ is necessarily set to half or more of the thickness T ₁ of the heat shield plate 1. do not have to. For example, the larger the thickness T ₁ of the this heat shield plate 1, 1/3 or more of the thickness _{T 1 (H 10 ≧ T 1} /
3) In some cases, securing them is sufficient. On the other hand, the recess 11
Has a size such that the cylindrical portion 12 formed on the inner peripheral edge of each of the washers 5, 5 can be inserted. The recess 11
Need to be formed over the entire circumference in order to accommodate the cylindrical portion 12, but the projection 10 need not necessarily be formed over the entire circumference. It may be formed intermittently at a plurality of places in the circumferential direction.

Each of the buffer elements 4c, 4c as described above is
The outer diameter is 0.08 to 0.20 mm, preferably 0.10 to
A material formed by braiding a 0.15 mm stainless steel filament is further molded under pressure to give an apparent bulk density of 0.12-0.
20, preferably 0.14 to 0.18. When the outer diameter of the filament is less than 0.08 mm, the rigidity of the filament becomes too low, and it becomes difficult to obtain the elasticity required for the cushioning elements 4c, 4c. It becomes difficult to maintain the damping effect.
On the other hand, when the outer diameter of the filament exceeds 0.20 mm, the rigidity of the filament becomes too high, and the rigidity of each of the buffer elements 4c and 4c becomes too high.
The damping effect is reduced. The outer diameter is 0.08 to 0.20m
m, preferably 0.10 to 0.15 mm, a sufficient vibration damping effect can be obtained from the beginning to after a long period of time.

On the other hand, if the apparent bulk density is less than 0.12, the porosity is too high, so that it is deformed by a very light force, and the elasticity required for the cushioning elements 4c, 4c is obtained. It becomes difficult to maintain a sufficient damping effect over a long period of time. On the other hand, when the apparent bulk density exceeds 0.20, the porosity is too low, and the force required for deformation increases, and the respective buffer elements 4c,
The rigidity of 4c is too high, and the vibration damping effect is low. The apparent bulk density is 0.12 to 0.20, preferably 0.1
If it is regulated to 4 to 0.18, a sufficient vibration damping effect can be obtained from the beginning to after a long period of time. Furthermore, each of the buffer elements 4c, among 4c, the thickness T _4c of the portion excluding the projection portion 10 and 10, 2 to 5 mm in an assembled state as shown in FIG. 1, preferably 3-4 mm. If the thickness T _4c is too small, the rigidity becomes too high, and if it is too large, the rigidity becomes too low. In any case, it is difficult to obtain a sufficient vibration damping effect over a long period of time. .

The ratio of the thickness T _4c in the assembled state to the thickness in the free state is about 0.85 to 0.95. When this ratio is too small (when the compression amounts of the respective buffer elements 4c and 4c accompanying the assembly are too large),
The rigidity of each of the cushioning elements 4c, 4c becomes too high, and the damping effect is reduced. On the other hand, when the ratio is too large (when the compression amount of each of the buffer elements 4c and 4c due to the assembling is too small), not only the support rigidity of the heat shield plate 1 becomes too low, but also the length becomes long. When each of the cushioning elements 4c, 4c is damaged by use over a period, the heat shielding plate 1
There is a possibility of rattling. Each of the above-mentioned numerical values is a light heat shield plate 1 for attaching the present invention to an exhaust manifold or a turbocharger of an automobile engine.
The case where it is used for supporting is shown. When the present invention is applied to supporting a heavy heat shield plate used for other purposes, the above numerical values are designed in accordance with the weight of the heat shield plate and the like.

Each of the cushioning elements 4c, 4c as described above is provided such that each of the projections 10 is provided between the inner peripheral edge of the mounting hole 2 and the sleeve 3.
In the annular gap 13 between the outer peripheral surface of the
Of the buffer elements 4c, 4c, and the leading edges of the projections 10, 10 of the buffer elements 4c, 4c are abutted or closely opposed to each other at the axial center of the annular gap 13 to constitute the buffer unit 8. are doing. Each of the above convex portions 10, 10
Even if the height H ₁₀ in the free state is greater than half the thickness T ₁ of the hot plate 1 shielding the, each protrusion 10, 1
Since 0 is elastically deformed, there is no particular problem.

A coupling member (not shown) such as a bolt or a stud is inserted through the sleeve 3 supported through the buffer unit 8 inside the mounting hole 2 as described above. A screw hole or a nut formed in a mounting portion provided on the exhaust manifold or the turbocharger is screwed together and further tightened. In this state, the sleeve 3 is strongly clamped between the outer end surface of the mounting portion and the head or nut of the bolt, and is fixed to the mounting portion. At the same time, the buffer elements 4c, 4c constituting the buffer unit 8 are elastically compressed between the front and back surfaces of the heat shield plate 1 and the washers 5, 5, so that the heat shield plate 1 It is supported in a buffered manner by the mounting portion. Since the sleeve 3 is stretched between the outer end surface of the mounting portion and the head or nut of the bolt,
The buffer elements 4c and 4c are not excessively compressed.

According to the heat shield plate supporting apparatus of the present invention configured as described above, the annular shape between the inner peripheral edge of the mounting hole 2 formed in the heat shield plate 1 and the outer peripheral surface of the intermediate portion of the sleeve 3. Gap 1
In 3, there are convex portions 10, 10 provided on a pair of buffer elements 4 c, 4 c constituting the buffer unit 8. Each of these convex portions 10 and 10 also
Like other parts of c and 4c, it has many minute gaps inside and is elastically deformable. For this reason, each of the above-mentioned convex portions 10, 10
However, it is possible to prevent the inner peripheral edge of the mounting hole 2 and the outer peripheral surface of the intermediate portion of the sleeve 3 from directly contacting each other, thereby reliably preventing chattering noise.

Further, since the buffer elements 4c and 4c having the same shape are used, the cost can be reduced by simplifying manufacturing and parts management. Moreover, each of the convex portions 10,
The height H10 of ₁₀ is limited, and there is no portion in each of the cushioning elements 4c, 4c that is long in the axial direction and has a small thickness in the diameter direction. Therefore, the work of uniformly processing the densities of the buffer elements 4c and 4c to a desired value over the whole including the convex portions 10 and 10 can be easily performed.

Further, at the time of assembling, the protrusion 10 having a small axial dimension is connected to the inner peripheral edge of the mounting hole 2 and the sleeve 3.
Only need to be inserted into the annular gap 13 between the outer peripheral surface of the intermediate part. As in the conventional structure shown in FIG. 4 described above, there is no need to insert the small-diameter portion 7 having low rigidity and being long in the axial direction inside the other buffer element 4a. For this reason, the assembling work is easy, and the cost can be reduced from the viewpoint of the efficiency of the assembling work. As shown in FIG. 1, the sleeve 3 and a pair of buffer elements 4c, 4c and washers 5, 5 are mounted on the buffer plate 1, and the outer peripheral edges of both ends of the sleeve 3 (see FIG. 1). (α, β portions) can be swaged outward in the diameter direction to prevent the sleeve 3 from being separated from the washers 5, 5. With this configuration, the buffer plate 1 and the sleeve 3, the buffer elements 4c, 4c, and the washers 5, 5 can be integrally handled, and the handleability and assemblability of the buffer plate 1 are improved. Can be achieved.

[0022]

According to the present invention, a supporting device for a heat shield plate that can exhibit stable performance without generating vibration noise can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a view showing an example of an embodiment of the present invention and corresponding to an enlarged cross section AA in FIG. 2;

FIG. 2 is a perspective view showing an example of a heat shield plate.

FIG. 3 is a view similar to FIG. 1, showing a first example of a conventional structure.

FIG. 4 is a view similar to FIG. 1, showing the second example;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 heat shield plate 2 mounting hole 3 sleeve 4, 4 a, 4 b, 4 c buffer element 5 washer 6 large diameter part 7 small diameter part 8 buffer unit 9 main part 10 convex part 11 concave part 12 cylindrical part 13 annular gap

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G004 AA01 BA04 DA15 EA03 EA05 FA01 FA04 3J066 AA01 AA26 BA01 BB01 BC03 BD07 BE05

Claims (1)

[Claims] 1. A cylindrical sleeve is supported inside a circular mounting hole formed in a heat shield plate via an elastic buffer unit, and the heat shield plate is mounted by a coupling member inserted through the sleeve. In the support device for a heat shield plate, which is supported in a buffered manner, the buffer unit is formed by combining a pair of buffer elements each having an annular shape and the same shape in a state of being symmetrically arranged with respect to the axial direction. Each of these buffer elements has, on the inner peripheral edge of the surface facing each other, a convex portion whose height is smaller than the thickness of the heat shield plate and which can enter the inside of the mounting hole. Each of the shock-absorbing elements is formed by inserting each of these convex portions into an annular gap between the inner peripheral edge of the mounting hole and the outer peripheral surface of the intermediate portion of the sleeve from both ends of the mounting hole. , Constituting the above buffer unit A support device for a heat shield plate.