JP4459070B2 - Tubular member structure - Google Patents

Description

  The present invention relates to a cylindrical member structure that is provided as a heat insulating material around a pipe such as an exhaust gas recirculation pipe for extracting a part of exhaust gas from an engine exhaust side of a vehicle body and sending the exhaust gas to the intake side. .

In an automobile engine or the like, an exhaust gas recirculation (hereinafter referred to as EGR) system is used as an exhaust gas purification system. This EGR system extracts a part of the exhaust gas from the exhaust side, returns it to the intake side, and suppresses the combustion of fuel in the engine with the exhaust gas returned to the intake side to lower the combustion temperature, Generation of NOx (nitrogen oxide) is reduced.
When performing this type of EGR, there is an EGR pipe between the appropriate position of the exhaust passage extending from the manifold exhausted from the engine to the exhaust pipe and the appropriate position of the intake passage extending from the intake pipe to the intake manifold of the engine. The exhaust gas is recirculated through the EGR pipe.

As described above, since the EGR pipe is connected to the manifold connected to the engine as the combustion section, the heat of the engine and the heat of the exhaust gas are transmitted to become high heat. For this reason, when the EGR pipe is touched during the work of the vehicle or the like, the worker may be burned, and in order to prevent this, the EGR pipe may be covered with a heat insulating material. To prevent such a situation, JP-A-2003-049 9 81 No. techniques, by winding a metal strip spirally formed in a cylindrical shape, a heat insulating material which is disposed such as glass wool inside Is disclosed.

JP 2003-049981 A JP 2002-188526 A

Assembling of the cylindrical member consisting of such a cylindrical body (metal part) and glass wool is done with an adhesive, but if it is placed in a hot part like an EGR pipe, the adhesive is denatured by heat and bonded. Power may be lost. Since the EGR pipe is directly connected to the engine part, when the vibration is transmitted to the EGR pipe, the glass wool separated from the cylinder part body is displaced in the axial direction of the cylinder part body, and the glass wool protrudes from the end part of the cylinder part body. Sometimes. When glass wool protrudes from the cylindrical body, the heat insulating property of the cylindrical member is lost. In particular, the glass wool may fall off due to the gravitational action at a location where the cylindrical member is disposed in a portion where the EGR pipe is inclined in the vertical direction.
Furthermore, since glass wool has a rectangular sheet piece rounded into a cylindrical shape, when it protrudes from a cylindrical member, the cylindrical cut (matching portion) portion of the glass wool spreads and passes through the EGR pipe. There was a problem that dropped out.
The present invention has been made in view of such circumstances, and a cylindrical member that prevents a displacement between the main body portion of the cylindrical member and the heat insulating material even if the adhesive is peeled off or no adhesive is used. To provide a structure.

In order to achieve the above-described object, the present invention provides a cylindrical shape by winding a metal strip in a spiral shape, and a spiral or ring-shaped projection having a wavy cross section in the longitudinal axis direction on its peripheral wall. A cylindrical member comprising a cylindrical main body formed continuously in a cylindrical arrangement and a heat insulating material disposed inside the cylindrical main body, on the entire circumference of the end of the cylindrical main body over circumferential crushed part plurality of axial line shape having a spacing is formed, and wherein the plurality of crushed portions that are bent radially inwardly to every other, the tubular body end the diaphragm portion of the petal shape is formed by the narrowed portion, before Symbol insulation is moved outward from the tubular body end, characterized in that it has to be regulated.
In a preferred aspect of the present invention, the metal strip is composed of a plurality of metal strips including an inner layer material and an outer layer material. More preferably, the inner layer material is made of aluminum or an aluminum alloy, and the outer layer material is made of stainless steel or a stainless alloy. Moreover, it is preferable that the said heat insulating material is glass wool.

According to the present invention, the plurality of axially crushed portions are formed at intervals in the circumferential direction over the entire circumference of the end portion of the cylindrical body , and one of the plurality of linearly crushed portions is provided. by being bent radially inwardly to every movement, the diaphragm portion of the petal shape is formed on the tubular body end, by the narrowed portion, before Symbol insulation outward from the tubular body end There since the so that is regulated, there is no heat insulating material comes out of the end of the tubular member. The cylindrical main body is formed by spirally winding a metal band material into a cylindrical shape, and on the peripheral wall portion, continuous strips having a wavy cross section in the longitudinal axis direction are continuously arranged in a spiral or ring shape. Since it forms in this , a cylinder part main body comes to have flexibility.
In addition , the petal-shaped throttle part forms a plurality of linear crushing parts crushed the uneven parts in the axial direction at the end part of the cylindrical part body, and the radial direction along the crushing part It can be easily formed by bending inward , and the band material can be prevented from being unwound.
In the present invention, the metal strip is composed of a plurality of metal strips including an inner layer material and an outer layer material. In particular, the inner layer material is made of aluminum or an aluminum alloy , and the outer layer material is stainless steel. Alternatively, an embodiment made of a stainless alloy is excellent in heat resistance, corrosion resistance, and heat retention, and is advantageous for being arranged in a high heat part, and an embodiment in which the heat insulating material is glass wool ensures heat insulating properties of the cylindrical member. This is advantageous.

Hereinafter, embodiments of the cylindrical member structure of the present invention will be described with reference to the drawings.
A cylindrical member 1 shown in FIG. 1 includes a cylindrical body 2 and a heat insulating material 3. The cylinder body 2 is a cylinder having a circular cross section, is formed of stainless steel and aluminum, aluminum is used for the inner layer material 4 shown in FIGS. 2A and 2C, and stainless steel is used for the outer layer material 5.
As shown in FIG. 2A, the inner and outer layer materials 4 and 5 are respectively formed on a side surface of a flat plate-like thin strip, wound spirally, and formed into a cylindrical shape. In addition, the cylindrical part main body 2 may be obtained by separately shifting and overlapping the strips of the inner layer material 4 and the outer layer material 5 as described above. You may wind spirally.

  As shown in FIGS. 2B and 2C, spiral or ring-shaped uneven portions 6, 7 are continuously formed in the axial direction of the tubular body 2 on the peripheral wall portion of the tubular member 1 by a well-known technique. To do. By forming the concave and convex portions 6 and 7, the cylindrical portion main body 2 has a linear cylindrical shape when no load is applied, but is curved when a load is applied, and returns to the original linear shape when the load is removed. It is formed in the elastic region. That is, it is an elastic body having flexibility only when a load is applied. In addition, although the cylinder part main body 2 was formed with stainless steel and aluminum, you may form with a kind of metal only of stainless steel or aluminum. Moreover, it is not necessary to form with two strips, and may be formed with one or three or more strips. As for the material, other metals such as iron and copper can be used.

  A tubular heat insulating material 3 is disposed on the inner peripheral portion of the tubular body 2. As the heat insulating material 3, glass wool resistant to heat is used, but other materials such as asbestos can be used as long as they are heat resistant and have a heat insulating effect (see B in FIG. 2). The heat insulating material 3 is formed in a cylindrical shape by attaching the opposing sides of a rectangular sheet-shaped member or strip. FIG. 1 shows a cut (seam) 11 portion of the heat insulating material 3. The cylindrical body 2 and the heat insulating material 3 are attached by an adhesive that is resistant to heat. However, if an adhesive is applied to the whole of the joint surfaces, the flexibility of the cylindrical body 2 is lost.

As shown in FIG. 1, the tubular member 1, one end or both ends of the cylindrical body 2 is bent partially folding, the shape of the opening is formed in the flower valve shape. Folding method, as shown in FIG. 3, the opposite end from the end portion of the cylindrical body 2 to the (axial) direction, a suitable width, for example, the crushed portion 8 crushed to about 10mm around linear, tubular A plurality of lines are formed at equal intervals in the circumferential direction of the main part 1. And as shown in FIG. 4, every other crushing part 8 is bent, and the bending part 9 bent in the radial direction inner side of the cylinder part main body 2 is formed. Thus an opening is formed in floral valve shape. Since these bent portions 9 are formed, it is possible to prevent the heat insulating material 3 from coming out of the end portion of the tubular portion main body 2 even if the adhesive force of the adhesive of the heat insulating material 3 is lost. In addition, since the cylindrical member 1 forms the crushing part 8 in an edge part, and bends, flexibility is lost, Therefore The bent shape of this part is maintained as it is .

  In the present embodiment, the inner diameter of the tube main body 2 is about 70 mm, and the outer diameter of the heat insulating material 3 is substantially equal to the inner diameter of the tube main body 2 and the thickness is about 5 mm. The bending portion 9 is bent so that the heat insulating material 3 does not come out of the opening in consideration of the thickness of the heat insulating material 3. Since the cylindrical member 1 is formed by winding a strip, when the strip is cut, the strip may be unwound from the cut portion and gradually increase, but the crushing portion 8 is formed. There is also an effect to prevent it from being unraveled.

Next, a specific usage example of the tubular member 1 will be briefly described.
FIG. 5 is a schematic view of an automobile engine unit. An air cleaner 34 is connected to the intake system side of the engine 31 via an intake pipe 32 and an intake manifold 33. An exhaust manifold 35 and an exhaust pipe 36 are disposed on the exhaust system side of the engine 31, and a catalytic converter 37 is connected to the middle of the exhaust pipe 36. An EGR pipe 38 is connected between the intake pipe 32 and the exhaust pipe 36 so as to straddle the engine 31.
As shown in the figure, a cylindrical member 1 is disposed around the EGR pipe 38. For convenience, the cylindrical member 1 is arranged in a straight portion, but the EGR pipe 38 is bent in a vertical direction, a front-rear direction, and a horizontal direction in many portions, and is actually arranged in the curved portion. Since the cylindrical member 1 has flexibility, it can be easily attached to a bent portion of the EGR pipe 38. By attaching the cylindrical member 1 to such a bent portion, the cylindrical member 1 tries to return to the original linear shape, and therefore the cylindrical member 1 can be fixed to the EGR pipe 38 by its elastic force. It is possible and does not require a separate mounting member.
In the straight portion of the EGR pipe 38, the tubular member 1 is disposed from the corner portion (or curved portion) to the corner portion of the pipe by utilizing the elastic force of the tubular member 1. Can be fixed. The EGR pipe 38 directly receives the vibration of the engine 31, but by using a glass wool or the like having a buffering property as the heat insulating material 3, this becomes a buffering material, and an abnormal noise due to the vibration can be obtained without using a special clamping material. And chatter noise can be prevented.

When the worker inspects the vehicle, the tubular member 1 is provided with the heat insulating material 3 on the inner peripheral wall thereof, so that it touches the EGR pipe 38 accidentally while starting the engine or immediately after stopping the engine. Even in this case, since the cylindrical member 1 is interposed, the worker plays a role as a protective material without being burned.
When the service life of the vehicle becomes long, the adhesive force of the adhesive is lost due to the influence of heat, and the heat insulating material 3 is peeled off from the tubular body 2. In such a case, the cylindrical member 2 and the heat insulating material 3 are likely to be displaced due to the vibration of the engine 31, but since the bent portion 9 is formed at the end of the cylindrical body 2, the heat insulating material 3 is restricted by the bent portion 9 and does not come out of the tube body 2. Therefore, as in the conventional case, the heat insulating material 3 is displaced from the cylindrical body 2, the cut 11 (see FIG. 1) of the heat insulating material 3 spreads, the cut 11 passes through the EGR pipe 38, and the cylindrical member 1 falls off. Is prevented. In particular, when the cylindrical member 1 is disposed in the EGR pipe 38 extending in the vertical direction, the heat insulating material 3 is easily dropped due to gravity and vibration, so that the effect is remarkable. In addition, when arrange | positioning the cylindrical member 1 to an up-down direction, what is necessary is just to form a bending part only in the lower end part of the cylindrical member 1. FIG.

FIG. 6 shows a structure in which a bellows portion 40 is formed at the base of the EGR pipe 38. The bellows portion 40 is provided in order to improve heat dissipation and bendability of the pipe 38. A cylindrical member 1a having a large diameter is disposed in the bellows portion 40, and a cylindrical member 1b having a small diameter is disposed in a portion of the normal pipe 38. When the cylindrical member 1a is arranged in a portion having a large diameter in this way, the heat insulating material 3 peeled from the cylindrical portion main body 2 easily moves toward the smaller diameter, but a bent portion (not shown). 9 is formed, its movement is restricted.

Next, an example of use of the cylindrical member 1 other than the EGR pipe 38 will be shown.
An exhaust manifold 35 is connected to the exhaust system side of the automobile engine 31 shown in FIG. 7 , and exhaust pipes 36a and 36b are connected to the exhaust manifold 35 so as to sandwich a catalyst portion 37 for purifying exhaust gas. ing. A cylindrical member 1 is disposed around the exhaust pipe 36a on the one exhaust manifold 35 side. This tubular member 1 is disposed in the exhaust pipe 36a as a heat insulation cover for the exhaust gas, and contributes to an increase in the efficiency of the processing capacity of harmful substances (gas) such as graphite in the catalyst disposed inside the catalytic converter 37. To do. Even if the heat insulating material 3 is provided in such an exhaust pipe 36a, the bent portion 9 can prevent the heat insulating material 3 from falling off.

Although the embodiments of the present invention have been described above, the present invention is of course not limited thereto, and various modifications and changes can be made based on the technical idea of the present invention.
The usage of the cylindrical member 1 is not particularly limited to an automobile, and can be applied to a pipe connected to a prime mover such as an internal combustion engine or an external combustion engine.
The diameter of the cylindrical member 1, the thickness of the band-shaped member, the length of the cylindrical member, the height of the crests of the concavo-convex portion can be adapted to the use of the cylindrical member 1, and is not particularly limited.

It is a perspective view of the cylindrical member (state which has not applied load) in an embodiment of the invention. 2A is an enlarged cross-sectional view of the peripheral wall portion (before deformation of the concavo-convex portion) of the cylindrical member of FIG. 1, B is a partially broken cross-sectional view of the cylindrical member cut in the axial direction, and C is the peripheral wall portion of the cylindrical member. It is sectional drawing (after a deformation | transformation of an uneven | corrugated | grooved part). It is a perspective view which shows the whole cylinder part main body (state which added the load and curved) of FIG. It is an expansion perspective view of the bending part of the cylindrical member of FIG. It is a top view of the state which has arrange | positioned the cylindrical member of FIG. 1 to the EGR pipe. It is a top view of the state which has arrange | positioned the cylindrical member of FIG. 1 to the EGR pipe with a bellows. 1 shows a state in which a cylindrical member is disposed around the exhaust pipe of an automobile.

DESCRIPTION OF SYMBOLS 1 Cylindrical member 2 Cylindrical part main body 3 Heat insulating material 4 Inner layer material 5 Outer layer material 6 Concave part 7 Convex part 8 Crushing part 9 Bending part 11 Break 38 EGR pipe

Claims (4)

A cylindrical overlapping winding a metal strip in a spiral shape, the peripheral wall portion of its, the unevenness condition of the longitudinal axis of the cross-section forms a wave-like, formed by continuously formed in spiral or ring-shaped arrangement A cylindrical member composed of a cylindrical body and a heat insulating material disposed inside the cylindrical body ,
A plurality of axially crushed portions are formed at intervals in the circumferential direction over the entire circumference of the end portion of the cylindrical body , and the plurality of linearly crushed portions are arranged radially inwardly every other one. in that is bent, narrowed portion of the petal shape is formed on the tubular body end, by the narrowed portion, before Symbol insulation so that outward movement is restricted by the tubular body end A cylindrical member structure characterized by being made. The cylindrical member structure according to claim 1, wherein the metal strip is composed of a plurality of metal strips including an inner layer material and an outer layer material. Tubular member structure according to claim 2 the inner layer material is made of aluminum or an aluminum alloy, the outer layer material is characterized by a stainless or stainless alloy Tona Rukoto. The cylindrical member structure according to any one of claims 1 to 3 , wherein the heat insulating material is glass wool.

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