JP5370691B2 - Fuel delivery pipe, exhaust gas recirculation chamber, and methods of manufacturing the same - Google Patents

Description

  The present invention relates to a delivery pipe for delivering a fluid such as liquid fuel or exhaust gas, particularly a fuel supply pipe (fuel delivery pipe or exhaust gas recirculation (EGR)) attached to a cylinder head portion of an engine. The present invention relates to an exhaust gas distribution pipe attached to a chamber.

  A fuel delivery pipe for an automobile is a fuel passage for supplying fuel to a cylinder head portion such as an injector to which a spark plug is attached. Generally, an aluminum die-cast alloy, an iron (SUS) pipe, or the like is used. Engines that require high combustion pressure, such as direct injection engines that have been put into practical use in recent years, have a structure that can withstand combustion pressure and vibration by increasing the thickness of the fuel delivery pipe. However, the larger the wall thickness, the heavier it becomes, and adverse effects such as a decrease in fuel consumption have been a problem.

  Patent Document 1 proposes an “intake manifold” in which an intake pipe and a delivery pipe are combined, which suppresses the thickness of the delivery pipe and improves the assembly to the engine unit.

JP-A-9-217661

  The delivery pipe increases in weight as the wall thickness increases, which causes problems such as an increase in cost, a decrease in workability, an increase in fuel consumption, and the need for countermeasures against vibration. In addition, “biofuel” with a high alcohol concentration, which is used as an alternative fuel for gasoline in recent years, causes corrosion of aluminum and iron used in delivery pipes.

  The delivery pipe can be reduced in weight by casting a pipe member with an aluminum die-cast alloy or the like, and can have a structure capable of withstanding high pressure, but a delivery pipe having a corrosion-proofing effect against corrosive substances is not known.

SUMMARY OF THE INVENTION The present invention has as its main technical problem to provide a fuel delivery pipe having a superior anticorrosive property against a fuel having a high alcohol concentration, and capable of flexibly designing a fluid flow path at a low cost, and a method for producing the same. .

Fuel delivery pipe according to the present invention, and one or more pipe members containing iron as a main component, and one or more fluid outlet brazed connected to said pipe member, brazed to the pipe member An insert pipe having a fluid inlet connected thereto is molded into a die-cast alloy and is provided with a mounting boss , and a metal plating including a nickel-phosphorous plating layer is provided on the inner and outer surfaces of the insert pipe. The fluid outlet portion is an injector case, and the fluid inlet portion is a fuel inlet .

  According to the said structure, the channel | path of a fluid is ensured inside the pipe | tube with high sealing performance cast in the inside of a die-cast alloy. For this reason, compared with the case where the passage of the fluid is ensured only by casting, the manufacturing process is simplified and the fluid leakage due to the cast hole does not occur. Furthermore, since the shape of the insert pipe before casting is easy to process, it can be processed into a complicated shape. And, by forming a metal plating layer or a paint film having a high anticorrosion effect on the fluid circulating in the pipe in advance on the inner surface of the insert pipe serving as a fluid passage, for example, high-concentration alcohol or highly corrosive The anticorrosive property against the substance can be increased.

  The delivery pipe according to the present invention can also be applied to a fuel delivery pipe attached to a cylinder head of an engine by using an injector case as a fluid outlet and a fuel inlet as a fluid inlet.

  Also, it can be applied to an exhaust gas recirculation (EGR) chamber that recirculates exhaust gas from the engine by making the fluid outlet part an intake pipe connection case and the fluid inlet part an exhaust gas inlet. it can. In this sense, the fluid includes, for example, both engine fuel and other liquids such as gasoline and biofuel, and gas such as exhaust gas. The EGR chamber is a system for returning exhaust gas to the intake air of the engine again, and reduces the emission amount of nitrogen oxide (NOx) and further improves the fuel consumption.

  Further, the delivery pipe preferably has a metal plating layer on the outer surface of the insert pipe and at least one of a paint film on the outer surface of the delivery pipe. As a result, the corrosion resistance can be enhanced against external corrosion factors of the insert pipe, and the corrosion resistance of the insert pipe can be enhanced overall. For example, all halogen compounds such as calcium chloride sprayed to prevent rainwater and roads from freezing will erode die-cast alloys containing aluminum as the main component. Then, there is a problem that erosion reaches the outer surface of the delivery pipe. Even in such a case, erosion of the delivery pipe can be prevented if the outer surface of the insert pipe has a metal plating layer or a coating film of the coating on the outer surface of the delivery pipe.

  The metal plating layer formed on the inner or outer surface of the insert pipe is preferably a nickel-phosphorus plating layer. Nickel-phosphorous plating has not only corrosion resistance to substances containing alcohol, but also corrosion resistance to halogen compounds. For this reason, it has corrosion resistance with respect to both alcohol and a halogen by giving nickel-phosphorus plating to the inner surface and outer surface of an insert pipe simultaneously.

The paint used on the inner surface of the insert pipe or the outer surface of the delivery pipe is preferably a rust-proof surface treatment agent that does not contain chromium . This rust preventive surface treatment agent obtains a further excellent rust preventive effect by processing to a metal containing zinc or the like having a sacrificial anticorrosive effect without using chromium having environmental problems. Furthermore, it can be provided with further anticorrosion properties such as alcohol resistance by a combination with a material to be added and a surface treatment applied in advance.

  The sacrificial anticorrosive effect means an effect of protecting a high material by preferential corrosion of a low material when a material having a high oxidation-reduction potential is combined with a low material. Since the main component of the insert pipe is iron, zinc, chromium, manganese, zirconium, aluminum, titanium, magnesium, and the like are listed as materials having a lower potential than iron. Here, the oxidation-reduction potential is a scale for quantitatively evaluating the ease of electron emission or reception of the target substance.

The method for manufacturing a delivery pipe according to the present invention includes a step of brazing and connecting one or a plurality of molded pipe members 1 and a molded fluid outlet portion 2, and the fluid inlet portion molded with the pipe member 1. Forming the insert pipe 4, including a step of brazing and connecting 3, and a step of forming a metal plating layer 7 on at least the inner surface of the pipe member 1;
And a step of casting the insert pipe 4 into a molten die-cast alloy 5.

  According to the said structure, intensity | strength can be ensured without increasing the thickness of a main body, and since manufacture becomes easy, manufacturing cost can be reduced.

  In the above configuration, the step of forming the metal plating layer on the insert pipe is preferably performed by an electroless plating method. For example, in the case of nickel-phosphorus plating, the insert pipe is immersed in a plating solution containing a reducing agent such as hypophosphite, and the metal ions in the plating solution are deposited on the surface of the insert pipe by oxidizing the reducing agent. Can be deposited as According to the electroless plating method, the surface roughness of the surface of the insert pipe can be sufficiently reduced. For this reason, not only is the adhesion at the time of casting improved, but also the airtightness can be improved when applied to a product that requires a pressure-resistant sealing property such as an O-ring.

  The method for manufacturing a delivery pipe according to the present invention includes a step of brazing and connecting one or a plurality of molded pipe members 1 and a molded fluid outlet portion 2, and the fluid inlet portion molded with the pipe member 1. A step of forming an insert pipe 4 including a step of brazing and connecting 3, a step of casting the insert pipe 4 into a die-cast alloy 5 containing molten aluminum as a main component, and at least an inner surface of the pipe member 1 And a step of forming a paint film 8 on the side surface.

  According to the said structure, intensity | strength can be ensured without increasing the thickness of a main body, and since manufacture becomes easy, manufacturing cost can be reduced.

  The delivery pipe according to the present invention is formed by casting a pipe member or the like having at least an inner surface subjected to surface treatment by metal plating into a die casting alloy as a base material, or casting into a die casting alloy as a base material. Since at least the inner surface of the insert pipe is painted, it not only has excellent anticorrosive properties against highly corrosive fluids, but also allows the weight of the base material to be reduced while maintaining strength and sealability, resulting in fuel efficiency Will also improve. In addition, in the manufacturing method, the shape of the insert pipe is lost after being molded by casting the insert pipe into a die-cast alloy as a base material after performing the surface treatment after forming the insert pipe or performing no treatment. Therefore, it is possible to ensure adhesion and airtightness with the base material.

Fig.1 (a) is the schematic which showed the basic composition of the delivery pipe based on this invention, FIG.1 (b) is the schematic of the insert pipe of Fig.1 (a). 2A is a cross-sectional view of a delivery pipe formed by drilling from conventional casting, and is a schematic view corresponding to the cross section AA of FIG. 1A. FIG. These are the cases where the metal plating layer is formed in the surface of an insert pipe, Comprising: It is the schematic of the arrow cross section of AA of Fig.1 (a). FIG. 3A is a cross-sectional view of a delivery pipe formed by drilling from a conventional casting, and is a schematic view corresponding to a cross section taken along line AA of FIG. Is a case where a coating film is formed on the surface of the delivery pipe, and is a schematic diagram of a cross-section taken along the line AA in FIG. 1 (a), and FIG. 3 (c) is an A diagram in FIG. It is the schematic of the cross section of -A, Comprising: It is the Example which formed the coating film of the antirust surface treating agent which does not contain chromium on the layer which has a sacrificial anticorrosive effect. FIG. 4 is a schematic view of an engine unit to which a fuel delivery pipe is applied, and is a view for explaining how fuel is supplied to a cylinder. Fig. 5 (a) is a basic configuration diagram showing the entire fuel delivery pipe with the injector case connected to the injector in front, and Fig. 5 (b) is a side view of the injector case connected to the injector. FIG. 5C is a basic configuration diagram showing the entire fuel delivery pipe with the connection portion of the injector case connected to the injector as the rear surface. FIG. 6 is a diagram showing a procedure for manufacturing a delivery pipe according to the present invention, in the case where a metal plating process is performed. FIG. 6A is a diagram showing a procedure for manufacturing an insert pipe, and FIG. 6B is a diagram showing a procedure for manufacturing a delivery pipe using the insert pipe manufactured according to FIG. 6A. FIG. 7 is a diagram showing a procedure for manufacturing a delivery pipe according to the present invention, in the case of applying a coating. FIG. 7A is a diagram showing a procedure for manufacturing an insert pipe, and FIG. 7B is a diagram showing a procedure for manufacturing a delivery pipe using the insert pipe manufactured according to FIG. 7A. FIG. 8 is a diagram schematically showing an EGR chamber and showing an outline of an engine unit to which the EGR chamber is applied.

(First embodiment)
FIG. 1 (a) is a schematic diagram showing the basic configuration of a delivery pipe according to the present invention, and FIG. 1 (b) is a diagram showing an insert pipe inserted into the derivative pipe of FIG. 1 (a). is there.

  A delivery pipe 10 shown in FIG. 1A is configured by casting an insert pipe 4 into an aluminum die cast 5. The inner surface of the insert pipe 4 has either a metal plating layer 7 or a paint film 8. The aluminum die casting 5 is not particularly limited as long as it is a die casting alloy containing aluminum as a main component. In particular, an Al-Si-Cu alloy (ADC12) excellent in mechanical properties and castability, mechanical It is preferable to use an Al—Si—Cu alloy (ADC10) or the like excellent in properties and machinability. Further, Al-Si alloy (ADC1) excellent in castability and corrosion resistance, Al-Si-Mg alloy (ADC3) superior in mechanical properties to ADC1, and Al-Mg alloy (ADC5) excellent in corrosion resistance. Al-Mg-based alloy (ADC6) excellent in castability and corrosion resistance and Al-Si-Cu-based alloy (ADC14) excellent in wear resistance can also be used. Moreover, although aluminum die casting was illustrated, it is good also as other die-casting materials, such as zinc die-casting and magnesium, instead of aluminum die-casting.

  The insert pipe 4 shown in FIG. 1B shows a configuration in which three pipe members 1 and three fluid outlet portions 2 are alternately connected to the fluid inlet portion 3. The pipe member 1, the fluid outlet portion 2 and the fluid inlet portion 3 are all composed mainly of iron, and alloy steels and carbon steels including chrome steel, manganese steel, nickel chrome steel, nickel chrome molybdenum steel, and other stainless steels. The kind is not ask | required.

  The insert pipe 4 has an advantage that it can be easily formed into a required size and shape, in particular, a fluid flow path and an outer surface shape before casting into the aluminum die casting 5. Thus, for example, by bending a pipe member in a certain portion, the shape of the aluminum die casting can be finely formed, while maintaining the strength of the delivery pipe according to the present invention, thereby reducing the size and weight. It becomes possible. Therefore, the material of the pipe member 1, the fluid outlet part 2, and the fluid inlet part 3 is preferably low cost and excellent in workability.

  The surface of the insert pipe 4 preferably has a metal plating layer, particularly a nickel-phosphorous plating layer formed by an electroless plating method. The nickel-phosphorous plating layer has an advantage of high anticorrosion properties against alcohol or the like.

  The plating methods include conventional electrolytic plating and electroless plating. In electrolytic plating, the base material (insert pipe) is placed in the plating solution as a negative (negative) electrode, and the metal in the plating solution is energized. Ions are deposited as a metal layer on the surface of the base material.

  In electroplating, it is possible to select the presence or absence of luster, and processing such as bending and soldering after plating is superior to other plating, but the base material to be plated must be a conductive material, etc. However, depending on the shape of the base material, a uniform plating layer cannot be generated.

  In contrast, in electroless plating, the base material to be plated is placed in a plating solution containing a reducing agent such as hypophosphite, and the metal ions in the plating solution are removed from the surface of the base material by oxidizing the reducing agent. To be deposited as a metal layer.

  In electroless plating, the base material to be plated can be applied to non-conductive materials such as plastics, and the adhesion of the metal film to the target base material is superior to that of electrolytic plating. There is an advantage that a film can be formed. Furthermore, since there are fewer work steps than electrolytic plating, the formation of a metal film is fast, and it can be processed in large quantities in terms of equipment, it is suitable for mass processing at a lower cost than electrolytic plating.

  Electroless nickel-phosphorus (Ni-P) plating is a plating method that uses a hypophosphite reducing agent to reduce and deposit a nickel-phosphorous alloy on the base material to be plated to form a coating. The film thickness of the plating is formed uniformly. Since the nickel-phosphorous plating layer contains phosphorus (P), the nickel-phosphorous plating layer has an anticorrosion property superior to the “nickel plating layer” that does not contain phosphorus against organic substances, salts containing halogens, organic solvents, caustic alkalis, etc. There is an advantage that the hardness is higher than that of the nickel plating layer and the wear resistance is also excellent.

  Electroless nickel-phosphorus plating is excellent in adhesion to aluminum die casting, and it is possible to obtain a complicated shape and dimensional accuracy. From such characteristics, electroless nickel-phosphorus plating is suitable as a surface treatment for a portion that requires pressure-resistant sealing properties such as an insert pipe.

  Therefore, with this electroless nickel-phosphorous plating layer, this delivery pipe can suppress the deterioration of quality and performance even when using a high concentration of alcohol or the like, and can extend the life.

  Here, the melting point of the nickel-phosphorous plating layer is about 890 degrees (° C.), the melting point of aluminum which is the main component of the aluminum die casting is about 660 degrees (° C.), and the iron which is the main component of the pipe member Since the melting point is about 1500 degrees (° C.), it is possible to cast an insert pipe having a nickel-phosphorous plating layer on the entire surface (inner surface and outer surface) by aluminum die casting. In this delivery pipe, the insert pipe It is preferable to have a nickel-phosphorous plating layer on the entire surface. Thereby, the corrosion resistance of the insert pipe can be enhanced comprehensively from the inner surface and the outer surface.

Further, the inner surface of the insert pipe 4 preferably has a coating film of a paint, in particular, a coating film of a rust preventive surface treatment agent (for example, ZEC-888 or the like) that contains a silicate compound or the like but does not contain chromium. . The rust preventive surface treatment agent does not use chromium having environmental problems, and particularly improves the rust preventive property by the treatment to galvanizing or the like having a sacrificial anticorrosive effect. Further, by adding a material excellent in corrosion resistance, alcohol resistance and chemical resistance, for example, a fluororesin and a zirconium compound, to the paint containing the rust preventive surface treatment agent, a further anticorrosive effect is obtained. .

  The paint refers to a material that is applied to the surface of the base material in order to protect the target base material, provide beauty, and provide a unique function. The paint is generally liquid and protects the target base material by forming a coating film on the surface of the target base material by volatilization and drying of the solvent, or by allowing the paint components to penetrate inside the target base material. Or adjusting its beauty. The paint used in the present invention is an anti-corrosion, anti-corrosion, anti-mold, anti-ant, anti-fouling, waterproof, sterilization, chemical resistance, fire resistance, electromagnetic wave shielding, etc., oil paint, natural resin paint, fluororesin paint Synthetic resin paints, emulsion paints, composite paints thereof, composite layers thereof, and the like can also be used.

Painting refers to applying paint to the target base material. There are various coating methods such as brush coating, roller coating, spray coating, airless spray, roll coater, dip and spin, baking coating, dip coating, electrodeposition coating, electrostatic coating, powder coating, and UV curable coating. It can be appropriately changed depending on the material, size and shape of the target base material. As a coating method for a rust-proof surface treatment agent that does not contain chromium , for example, ZEC-888, dip and spin can be applied. Dip & Spin is a coating method in which the object to be coated in a bucket or the like is immersed in the paint bath together with the bucket, then the bucket is lifted and rotated, and excess paint is blown off by centrifugal force to obtain a uniform coating film. .

Here, the melting point of the coating film of the anticorrosive surface treatment agent not containing chromium is about 230 degrees (° C.), the melting point of aluminum, which is the main component of the aluminum die casting, is about 660 degrees (° C.), and the pipe Since the melting point of iron, which is the main component of the member, is about 1500 degrees (° C.), it is necessary to paint the required part after casting the insert pipe with aluminum die casting. With this delivery pipe, That is, it is preferable to have the coating film of the antirust surface treating agent on the inner surface of the insert pipe and the outer surface of the delivery pipe. Thereby, the corrosion resistance of the delivery pipe can be enhanced comprehensively from the inner surface and the outer surface.

  2A is a cross-sectional view of a delivery pipe formed by drilling from conventional casting, and is a schematic view corresponding to the cross section AA of FIG. 1A. FIG. These are the cases where the metal plating layer 7 is formed in the surface of an insert pipe, Comprising: It is the schematic of the arrow cross section of AA of Fig.1 (a).

  2 (a) and 2 (b) are schematic views using the same aluminum die casting, and comparing them, it can be seen that the delivery pipe according to the present invention is smaller overall.

  FIG. 3A is a cross-sectional view of a delivery pipe formed by drilling from a conventional casting, and is a schematic view corresponding to a cross section taken along line AA of FIG. These are the cases where the coating film 8 of the paint is formed on the surface of the delivery pipe, and is a schematic view of the cross section taken along the line AA of FIG. 1 (a), and FIG. It is the schematic of the arrow cross section of AA of a), Comprising: It is the Example which formed the coating film 8 of the coating material on the layers 6a and 6b which have a sacrificial anticorrosive effect.

  3 (a), 3 (b), and 3 (c) are schematic views using the same aluminum die casting, and comparing them, the delivery pipe according to the present invention is generally smaller. I understand that.

  In the conventional delivery pipe, in order to obtain the high pressure resistance, the thickness around the fluid flow path (inner surface) had to be thicker than a certain standard. However, in the delivery pipe according to the present invention, the high pressure resistance By preparing a pipe for use in advance and casting the pipe, the wall thickness around the fluid flow path can be made thinner than that of a conventional delivery pipe, thereby reducing weight and space.

  In FIG.3 (c), the coating film of the rust preventive surface treating agent which does not contain chromium is formed on the layer which has the sacrificial anticorrosive effect containing galvanization etc. FIG. This prevents intrusion of moisture that causes rust from the inner surface of the insert pipe and the outer surface of the delivery pipe, while suppressing the elution of the layer having the sacrificial anticorrosive effect, and maintaining the sacrificial anticorrosive effect stably for a long time. Corrosion due to rust can be prevented.

(Second Embodiment)
The delivery pipe according to the present invention is particularly applicable as a fuel supply pipe (fuel delivery pipe) attached to a cylinder head portion of an engine. Therefore, this usage form will be described first.

  FIG. 4 is a schematic diagram when the delivery pipe described in the first embodiment is applied to a fuel delivery pipe. As shown in this figure, the fuel delivery pipe 20 and the fuel tank 25 are connected in an annular shape by pipes 29 (29a to 29e), and a fuel pump 23 for sending out fuel, a pressure regulator 26, and the like are connected. The pressure regulator 26 is also connected to the intake manifold 33 through a pipe 29f.

  Although three injectors 21 are connected to the fuel delivery pipe 20, each injector 21 is connected to one intake manifold 33 corresponding to each injector and also connected to the engine computer 28 via electric wires. Has been.

  In FIG. 4, the fuel in the fuel tank 25 is supplied by the fuel pump 23 to each injector 21 of the fuel delivery pipe 20 via the fuel filter 22, and the intake manifold 33 is passed from the injector 21 by a signal from the engine computer 28. Through the cylinder (head portion).

  The pressure regulator 26 is a device for controlling the gasoline injection pressure of the injector 21 at a constant level. By returning the fuel in the fuel delivery pipe 20 to the fuel tank 25, the pressure of the intake manifold 33 and the fuel delivery pipe are increased. The difference of 20 fuel pressures is kept constant.

  FIG. 5A to FIG. 5C are views showing the basic configuration of the fuel delivery pipe 20 shown in FIG. FIG. 5A is a front view illustrating the connection portion of the injector case to the injector as a front surface, FIG. 5B is a side view, and FIG. 5C is a rear view. In addition, the broken line shown to Fig.5 (a) and FIG.5 (b) has shown the external shape of the insert pipe 4 inserted.

  As described above, the fuel delivery pipe 20 is configured by casting the insert pipe 4 into the aluminum die casting 5. The inner surface of the insert pipe 4 has either a metal plating layer 7 or a paint film 8. The surface of the aluminum die casting 5 is provided with a plurality of through holes for connection to an internal insert pipe, a fuel inlet 13 for injecting fuel into the fuel delivery pipe 20, and an injector case for delivering fuel to the injector 21. 12 is configured. An attachment boss 16 is provided as a screw hole for attaching the main body of the fuel delivery pipe 20 to the engine portion. The fuel inlet 13 is connected to a fuel filter 22 and a fuel pump 23, and the injector case 12 is connected to the injector 21.

  As described above, the structure in which the pipe member is cast therein can ensure sufficient strength as a fuel delivery pipe attached to a cylinder head portion of an engine having a high combustion pressure such as a direct injection engine.

  The fuel supplied by the fuel pump 23 passes through the internal pipe member 1 and the injector case 12 from the fuel inlet 13 and is sent to each injector case 12.

  Although a method for manufacturing the fuel delivery pipe 20 will be described later, there is an advantage that the fuel flow path can be flexibly formed in advance in a state before being cast by the aluminum die casting 5. For this reason, there exists an advantage which can be applied to the engine of various shapes. In addition, there is an advantage that the weight can be reduced as compared with a conventional delivery pipe by casting, and an improvement in fuel consumption of the engine is also expected.

Further, the inner insert pipe is excellent in corrosion resistance against alcohol or the like by surface treatment such as nickel-phosphorous plating or coating of a rust-proof surface treatment agent not containing chromium . For this reason, even if a high-concentration alcohol fuel is used, deterioration of its life can be suppressed.

  As described above, the delivery pipe according to the present invention can be applied to a fuel delivery pipe.

(Third embodiment)
FIG. 6 is a diagram showing a procedure for manufacturing a delivery pipe according to the present invention, in the case where a metal plating process is performed. FIG. 6A is a diagram showing a procedure for manufacturing an insert pipe, and FIG. 6B is a diagram showing a procedure for manufacturing a delivery pipe using the insert pipe manufactured according to FIG. 6A.

  As a manufacturing procedure of the insert pipe, first, the pipe member 1, the fluid inlet portion 3 and the fluid outlet portion 2 are formed into a necessary size and shape from the use of a sold product or a plate material (step S11). At this time, it is preferable that the diameters of the holes of the pipe member 1 and the fluid inlet portion 3 and the diameters of the side holes (holes) of the fluid outlet portion 2 are the same.

  Thereafter, the molded pipe member 1 and the molded fluid outlet 2 are alternately brazed (welded) by a necessary number (step S12). At this time, the side hole (connecting portion) of the fluid outlet portion 2 is matched with one hole (connecting portion) of the pipe member and connected without gap, and further connected to another side hole (connecting portion) of the fluid outlet portion 2. The necessary number of holes (connecting portions) of the pipe member and the side holes (connecting portions) of the fluid outlet portion 2 are alternately connected to the other hole (connecting portion) of the pipe member. At this time, it is also possible to connect the pipe member 1 so as to branch at the fluid outlet portion 2.

  Thereafter, the hole (connecting portion) of the fluid inlet portion 3 is matched with the hole (connecting portion) of the pipe member 1 and connected without gaps by brazing (step S13). (Step S14), and the insert pipe 4 is completed.

  In the conventional delivery pipe, the fuel flow path is formed by drilling the casting of the delivery pipe to form the flow path inside, but the formation of the flow path requires a complicated process. However, in the delivery pipe manufacturing method according to the present invention, an insert pipe is manufactured and cast in advance, so that a drilling step is not necessary for forming a flow passage. In addition, by providing a hole for penetrating the pipe member in the fluid outlet portion, a so-called skewered state may be secured and a necessary portion may be brazed and connected.

  The surface treatment of the metal plating is performed on at least the inner surface of the insert pipe serving as a distribution passage. Nickel-phosphorous plating is preferably used in order to improve the corrosion resistance against alcohol or the like. In this case, if an electroless plating method is used, a plating layer can be uniformly formed on both the inner and outer surfaces of the insert pipe.

  Depending on application, instead of nickel-phosphorous plating, nickel plating, chrome plating, zinc plating, cadmium plating, cadmium titanium plating, other plating, and Aldtex alpha (aluminized α), Alcast, Altech micron treatment A surface treatment or the like may be applied. If necessary, different types of surface treatment may be applied to the inner and outer surfaces of the insert pipe. Further, in the surface treatment of the insert pipe, a coating having various effects may be applied to a necessary portion, or the surface treatment and the coating may be combined.

  In the delivery pipe manufacturing method according to the present invention, the surface-treated insert pipe 4 is fixed inside the mold of the delivery pipe, and the insert pipe 4 is cast with a die-cast alloy containing aluminum as a main component (step) S15). Thereafter, unnecessary portions are cut, mounting bosses are formed, and other details are formed and cleaned, and further, inspections such as appearance and leakage are performed (steps S16 to S18).

  According to the delivery pipe manufacturing method as described above, the strength can be ensured without increasing the thickness of the main body, and the manufacturing can be facilitated, so that the manufacturing cost can be reduced. Further, not only the adhesion when cast by the surface treatment of the insert pipe is enhanced, but also the airtightness can be enhanced when applied to a product that requires a pressure-resistant sealing property such as an O-ring.

(Fourth embodiment)
FIG. 7 is a diagram showing a procedure for manufacturing a delivery pipe according to the present invention, in the case of applying a coating. FIG. 7A is a diagram showing a procedure for manufacturing an insert pipe, and FIG. 7B is a diagram showing a procedure for manufacturing a delivery pipe using the insert pipe manufactured according to FIG. 7A.

  As a manufacturing procedure of the insert pipe, first, the pipe member 1, the fluid inlet portion 3 and the fluid outlet portion 2 are formed into a necessary size and shape from the use of a sold product or a plate material (step S21). At this time, it is preferable that the diameters of the holes of the pipe member 1 and the fluid inlet portion 3 and the diameters of the side holes (holes) of the fluid outlet portion 2 are the same.

  Thereafter, the molded pipe member 1 and the molded fluid outlet 2 are alternately brazed (welded) in a necessary number (step S22). At this time, the side hole (connecting portion) of the fluid outlet portion 2 is matched with one hole (connecting portion) of the pipe member and connected without gap, and further connected to another side hole (connecting portion) of the fluid outlet portion 2. The necessary number of holes (connecting portions) of the pipe member and the side holes (connecting portions) of the fluid outlet portion 2 are alternately connected to the other hole (connecting portion) of the pipe member. At this time, it is also possible to connect the pipe member 1 so as to branch at the fluid outlet portion 2.

  Thereafter, the hole (connecting portion) of the fluid inlet portion 3 is matched with the hole (connecting portion) of the pipe member 1 and connected without gap by brazing (step S23), and the insert pipe 4 is completed.

  In the delivery pipe manufacturing method according to the present invention, since the insert pipe is manufactured in advance and the insert pipe is cast in the same manner as in the third embodiment, a drilling step is not necessary for forming the flow passage. In addition, by providing a hole for penetrating the pipe member in the fluid outlet portion, a so-called skewered state may be secured and a necessary portion may be brazed and connected.

  In the delivery pipe manufacturing method according to the present invention, the insert pipe 4 is fixed inside the mold of the delivery pipe, and the insert pipe 4 is cast with a die-cast alloy containing aluminum as a main component (step S24). Thereafter, unnecessary portions are cut, mounting bosses are formed, and other details are formed (step S25).

Thereafter, coating is performed on at least the inner surface of the insert pipe serving as a distribution passage, baking is performed on a necessary portion (step S26), cleaning is performed (step S27), and further, appearance, leakage, and the like are inspected (step S28). ), The delivery pipe 10 is completed. Here, in order to enhance the corrosion resistance against alcohol or the like, it is preferable to use a rust-proof surface treatment agent that does not contain alcohol-resistant chromium .

Instead of the rust-preventing surface treatment agent not containing chromium , various paints may be used or a composite layer thereof may be used depending on the application. Pre-nickel plating, chrome plating, zinc plating, cadmium plating, cadmium titanium plating, nickel-phosphorus plating, other plating and surface treatment by mutual diffusion phenomenon such as Altech alpha (aluminized α), Alcast, Altech micron treatment, etc. And then the surface may be painted. If necessary, different types of coating and surface treatment may be applied to the inner surface of the insert pipe and the outer surface of the delivery pipe. In the painting and surface treatment, only necessary portions may be applied.

  According to the delivery pipe manufacturing method as described above, the strength can be ensured without increasing the thickness of the main body, and the manufacturing can be facilitated, so that the manufacturing cost can be reduced. Further, not only the adhesion when cast by the surface treatment of the insert pipe is enhanced, but also the airtightness can be enhanced when applied to a product that requires a pressure-resistant sealing property such as an O-ring.

(Fifth embodiment)
The structure of the delivery pipe according to the present invention can also be applied as an EGR chamber that supplies exhaust gas to the intake manifold.

  FIG. 8 is a diagram schematically showing an EGR chamber and showing an outline of an engine unit to which the EGR chamber is applied. In FIG. 8, the EGR chamber 50 is connected to the exhaust gas accumulation part 52 via three EGR valves 51 and a pipe 53. Here, one of the EGR valves 51 is connected to the intake manifold 33 through a pipe 54, but generally, the EGR valve and the intake manifold are a pair, and the other EGR valves are similar to each intake manifold. Connected in form. Each EGR valve is also connected to the engine computer 28 via an electric wire.

  In FIG. 8, a part of the gas discharged from the cylinder head portion is supplied to each EGR valve 51 of the EGR chamber 50 through the exhaust gas accumulation portion 52, and from the EGR valve 51 to the intake manifold according to a signal from the engine computer 28. 33.

  The EGR chamber 50 can flexibly form the exhaust gas flow path, and can be reduced in weight by making the required wall thickness thinner than the conventional one manufactured by forming the flow path in the casting by drilling. It can be applied to low-cost engines of various shapes, and it can be expected to improve the fuel consumption of engines using this. In addition, the EGR chamber 50 has excellent anticorrosion properties such as alcohol resistance and calcium chloride, so that the life of the EGR chamber 50 is deteriorated when using high-concentration alcohol fuel or in an environment where the antifreezing agent calcium chloride is sprayed. As a result, the performance deterioration of the engine part can be suppressed. When used as an EGR chamber, high-concentration alcohol resistance is not so much required, so the surface treatment of the pipe member is performed by performing surface treatment by mutual diffusion phenomenon such as alcast treatment instead of metal plating. Adhesion may be increased.

  In the delivery pipe according to the present invention, an insert pipe to be cast into an aluminum die cast is formed in advance with necessary requirements (material, size, shape, etc.), and the insert pipe is cast into an aluminum die cast, thereby making it smaller than before. Light weight and low cost. Furthermore, according to a use, corrosion resistance can be improved by performing metal plating, an alcast process, coating, etc. on the surface of the insert pipe. Therefore, the industrial applicability when the present invention is implemented is extremely large.

DESCRIPTION OF SYMBOLS 1 Pipe member 2 Fluid exit part 3 Fluid inlet part 4 Insert pipe 5 Aluminum die-casting 6a, 6b Layer with sacrificial anticorrosion effect 7 Metal plating layer 8 Paint coating 10 Delivery pipe 12 Injector case 13 Fuel inlet 16 Attachment Boss (Mounting screw hole)
20 Fuel Delivery Pipe 21 Injector 22 Fuel Filter 23 Fuel Pump 24 Fuel Pump Controller 25 Fuel Tank 26 Pressure Regulator 27 Various Sensors 28 Engine Computer 29a, 29b, 29c, 29d, 29e, 29f Pipe 31 Air Cleaner 32 Air Flow Meter 33 Intake Manifold 41 Cylinder 42 Piston 43 Piston arm 44 Valve 45 Spark plug 50 EGR chamber 51 EGR valve 52 Exhaust gas accumulation part 53, 54 Pipe

Claims (7)

One or more pipe members containing iron as a main component;
One or more fluid outlets brazed to the pipe member;
An insert pipe having a fluid inlet connected to the pipe member by brazing is molded into a die-cast alloy in a molded state ,
A mounting boss is provided, and a nickel-phosphorous plating layer is provided on the inner and outer surfaces of the insert pipe.
And having a metal plating layer containing
The fluid outlet is an injector case;
A fuel delivery pipe, wherein the fluid inlet is a fuel inlet . The fuel delivery pipe according to claim 1, further comprising a paint film on at least a surface on the inner surface side of the insert pipe. Fuel delivery pipe according to claim 1 or 2 coating of the paint is characterized in that it comprises a rust surface treatment agent containing no chromium. Brazing and connecting one or more molded pipe members (1) containing iron as a main component and the injector case;
Brazing and connecting the pipe member (1) and the molded fuel inlet;
A step of forming an insert pipe (4) including a step of forming a metal plating layer (7) on at least the inner surface of the pipe member (1);
Forming a metal plating layer including a nickel-phosphorous plating layer on the inner surface and outer surface of the insert pipe, and casting the insert pipe (4) into a molten die-cast alloy (5) ;
A method for producing a fuel delivery pipe, comprising: a step of providing a mounting boss . 5. The method for producing a fuel delivery pipe according to claim 4, further comprising a step of forming a paint film on at least the inner surface of the insert pipe . One or more pipe members containing iron as a main component;
One or more fluid outlets brazed to the pipe member;
A fluid inlet connected to the pipe member by brazing;
Is cast into a die-cast alloy in a molded state with an insert pipe,
A mounting boss is provided, and a nickel-phosphorous plating layer is provided on the inner and outer surfaces of the insert pipe.
And having a metal plating layer containing
The fluid outlet is an intake pipe connection case,
The fluid inlet is an exhaust gas inlet
An exhaust gas recirculation chamber comprising a configuration. Brazing and connecting one or more molded pipe members (1) containing iron as a main component and the injector case;
Brazing and connecting the pipe member (1) and the molded fuel inlet;
Forming a metal plating layer (7) on at least the inner surface of the pipe member (1);
Forming the insert pipe (4) including:
Forming a metal plating layer including a nickel-phosphorous plating layer on an inner surface and an outer surface of the insert pipe;
Casting the insert pipe (4) into the molten die cast alloy (5);
And providing a mounting boss
A method for manufacturing an exhaust gas recirculation chamber.

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