JP2008144713A - Fuel cooling device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cooling device and its manufacturing method capable of securely preventing a sacrificial material for a sacrificial protection layer formed on a surface of the fuel cooling device from intruding in the device with a simple structure. <P>SOLUTION: The fuel cooling device 10 comprises a device main body 1 with a zigzag channel Z formed, a first closing body 2 and a second closing body 3 for closing both end sides of the device. An endless projection 4 for surrounding end part openings 13a is formed on both of the end sides 13, 13 of the device main body 1 on which the end part openings 13a communicating with the zigzag channel Z face. Endless recesses 5, 5 are respectively formed in positions corresponding to the projections 4, 4 on side surfaces confronting the end sides 13, 13 of the device main body 1 out of the first and second closing bodies 2, 3, and the projections 4 and recesses 5 are engaged with each other. The sacrificial protection layer 6 formed of metal powder is formed on an outer surface of the fuel cooling device 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cooling device and a manufacturing method thereof.

  The surplus fuel that has not been burned by the internal combustion engine (engine) of the vehicle is returned to the fuel tank via, for example, a return pipe. The temperature of the fuel rises and is discharged as vapor from the fuel tank, leading to problems such as air pollution. Particularly in the case of a diesel engine, in an accumulator fuel injection system using a common rail, since the pressure is extremely high, a high temperature of the return fuel is a big problem.

  Therefore, as a technology for cooling the surplus fuel returned from the engine, a fuel cooling device having a flow path provided therein is used, and the heat is dissipated in the process of flowing the high temperature surplus fuel through the flow path of the cooling device. There is a technique for returning the surplus fuel whose temperature has decreased to the engine again. For example, a fuel cooling device disclosed in Patent Document 1 is an example.

  In the fuel cooling device described above, generally, a device main body (housing) provided with a flow path is extruded by an aluminum alloy (for example, an Al-Mn alloy), and both ends of the device main body facing openings that communicate with the flow path. On the side, a plate-like or box-shaped closing body provided with an inlet for taking in surplus fuel into the apparatus main body and an outflow hole through which the radiated surplus fuel flows out to the fuel tank side outside the apparatus is provided at both ends and in a high-temperature atmosphere. The cooling device is manufactured.

  By the way, the outer surface of the cooling device is made of a sacrificial material (for example, a metal powder such as an Al—Zn alloy) that is lower in potential than an aluminum alloy that is a base material of the device for the purpose of improving its corrosion resistance. Although the sacrificial anticorrosive layer is formed, the sacrificial anticorrosive layer is formed at the same time as the above brazing because the apparatus main body is extruded. More specifically, a brazing material (for example, Al-10% Si alloy) is applied to both ends of the apparatus main body or a closed body, and both are assembled with a jig, and in this posture, metal powder is applied to the outer surface of the cooling apparatus. By coating the body and then storing the cooling device in a high temperature furnace for a certain period of time, the brazing material and the sacrificial material are melt-cured, and the brazing treatment and the surface treatment are performed simultaneously.

JP-A-2005-315104

  When the fuel cooling device manufactured by the above manufacturing method is used, the Al—Zn alloy applied to the surface of the fuel cooling device penetrates into the device while melting in the furnace and hardens in the flow path, for example. The problem that it ends up has arisen. Of this Al—Zn alloy, the Zn component is particularly immersed in the return fuel flowing through the flow path, and the return fuel containing the Zn component is repeatedly returned to the engine, thereby clogging the injector of the engine. It was directly related to a decrease in durability. Such a problem also exists in the fuel cooling device disclosed in Patent Document 1.

  The present invention has been made in view of the above-described problems, and extrudes an apparatus main body, brazes a closing body on both end sides having openings communicating with an internal flow path, and In a fuel cooling device in which a sacrificial material is applied to the surface and a sacrificial anticorrosive layer is formed in a high temperature atmosphere, a fuel cooling device capable of reliably preventing the sacrificial material from entering the cooling device with a simple configuration; It aims at providing the manufacturing method.

  In order to achieve the above object, a fuel cooling device according to the present invention is a fuel cooling device mounted on a vehicle, and a plurality of partition walls extending in the same direction inside the box are arranged at intervals. An apparatus main body in which a meandering flow path is formed, and a first closing body and a second closing body that close both ends of the apparatus main body, and any one of the first closing body and the second closing body On the other hand, there are an inflow hole that communicates with the serpentine flow path and supplies return fuel flowing in from the internal combustion engine to the serpentine flow path, and an outflow hole through which the return fuel that has flowed through the serpentine flow path flows out of the apparatus body In the fuel cooling device in which a sacrificial anticorrosive layer made of metal powder is formed on the outer surface of the fuel cooling device, the end portions of the device main body facing the end openings communicating with the meandering flow path An endless ridge surrounding the opening is formed, and the first, first Among the closed bodies, an endless recess is formed at a position corresponding to the protrusion on the side surface of the apparatus body facing the end, and the protrusion and the recess are fitted to each other. It is what.

  The apparatus main body has, for example, a cylindrical shape with a rectangular cross section. Inside the apparatus main body, a plurality of partition walls extending in the longitudinal direction are arranged at intervals to define a plurality of linear flow paths. One meandering flow path is formed by communicating the end portions of these flow paths in a staggered manner. One end of the meandering flow path is an inflow side for high temperature return fuel returning from the internal combustion engine to flow into the apparatus main body, and the other end is the return fuel radiated in the process of flowing through the meandering flow path to the fuel tank outside the apparatus. It becomes the outflow side to return.

  The main body of the apparatus is generally formed by extruding a billet made of an aluminum alloy (generally an Al-Mn alloy). Therefore, at both ends, the apparatus body is formed into a shape facing an opening communicating with the internal flow path. The A closing body made of, for example, a plate-like or box-like aluminum alloy is brazed to both ends of the apparatus main body (for example, an Al-10% Si alloy is used as a brazing material), and an outer surface thereof, for example, Al-Zn is used. A sacrificial material (flux) made of metal powder such as an alloy is applied or sprayed, and the whole is placed in a high temperature atmosphere for a predetermined time, whereby the brazing material is melted and hardened, and the flux is melted and diffused to manufacture a cooling device.

  Here, in the fuel cooling device of the present invention, an endless ridge that faces the end side and surrounds the opening that communicates with the flow path is formed on both end sides of the device main body. For example, when five linear flow paths are formed inside the apparatus main body, five openings communicating with the respective flow paths are provided on both end sides of the apparatus main body (the cross-sectional shape is rectangular, square, or circular). However, endless protrusions (such as flat ring-shaped protrusions) are formed on the outer periphery of these five openings. Moreover, it is preferable that a plurality of fins for heat dissipation are formed on one side of the outer surface of the apparatus main body.

  On the other hand, an endless recess is provided, for example, at a position corresponding to the endless protrusion at the time of assembly on the side surface facing the apparatus main body, and the protrusion and the recess are fitted. It has become so. Preferably, the fitting strength can be increased by forming both of the endless ridges so that the line dimensions of the endless ridges are larger than the line dimensions of the recesses. When fitting both, the brazing material is applied to one or both of the ridges and recesses, and after both are fitted together, the sacrificial material is applied to the entire outer surface of the cooling device, and is kept in a high temperature atmosphere for a predetermined time. By placing, the brazing material and the sacrificial material are melt-cured, and the brazing treatment and the surface treatment are performed simultaneously.

  By forming an endless ridge that surrounds the opening on the end side of the apparatus body, forming an endless concave line that fits this ridge at the corresponding position of the closing body, and fitting both together, Even when the sacrificial material applied to the outer surface of the apparatus is melted, the intrusion of the sacrificial material is reliably prevented as a result of the molten sacrificial material being blocked from entering the apparatus (channel) by the endless protrusions. . Furthermore, since this fitting structure is a very simple structure, the manufacturing cost of the apparatus is not increased.

  Furthermore, when brazing the main body of the device and the closing body, the fixing jig that has been required in the past is unnecessary because both are fitted together, and a unique fixing jig is provided for each cooling device having a different shape and size. This also leads to a reduction in manufacturing costs.

  Further, in another embodiment of the fuel cooling device of the present invention, endless recesses surrounding the end opening are formed on both end sides of the apparatus main body facing the end opening communicating with the meandering flow path. And the form by which the endless protrusion is formed in the position corresponding to the said groove on the side surface which opposes the said end side of an apparatus main body among the said 1st, 2nd obstruction | occlusion body may be sufficient.

  Also in this embodiment, the apparatus main body and the closing body can be fitted together, and this fitting structure can surely prevent the molten sacrificial material from entering the apparatus main body.

  The fuel cooling device manufacturing method according to the present invention is a fuel cooling device mounted on a vehicle, wherein a plurality of partition walls extending in the same direction inside the box are arranged at intervals, and a meandering flow is provided. An apparatus main body in which a path is formed, and a first closing body and a second closing body that close both ends of the apparatus main body, and one of the first closing body and the second closing body. Are formed with an inflow hole that communicates with the serpentine flow path and supplies return fuel flowing from the internal combustion engine to the serpentine flow path, and an outflow hole through which the return fuel flowing through the serpentine flow path flows out of the apparatus body. A method of manufacturing a fuel cooling device in which first and second closing bodies are fitted to both end sides of an apparatus main body, wherein the apparatus main body is extruded and communicated with the meandering flow path. The endless opening that surrounds the end opening on both end sides of the device body facing the opening A device body is manufactured by forming a strip, and a concave strip is formed at a position corresponding to the protrusion on the side surface of the first and second closing bodies facing the end side of the device body. 1. A first step of manufacturing a second closing body, a brazing material is applied to at least one of the recess and the protrusion, and both are fitted together, and the first and second closing bodies are fitted to the apparatus main body. And a third step of coating the outer surface of the fuel cooling device with a metal powder and heat-treating the fuel cooling device.

  An endless recess surrounding the end opening is formed on both end sides of the apparatus main body facing the end opening communicating with the meandering flow path. Of the first and second closing bodies, the apparatus main body The manufacturing method is the same also in the case of the apparatus form in which the endless protrusion is formed in the position corresponding to the said groove on the side surface which opposes the said end side.

  According to the manufacturing method of the present invention, the assembly can be completed simply by fitting the apparatus main body and the closing body, and then the heat treatment process can be performed. Therefore, the jig fixing process can be omitted, and the yield is improved. be able to.

As can be understood from the above description, according to the fuel cooling device of the present invention and the manufacturing method thereof,
It is a component of the sacrificial material in the return fuel flowing through the meandering flow path in the fuel cooling device by reliably preventing the metal powder (sacrificial material) coated on the outer surface from entering the fuel device. It is possible to reliably prevent the occurrence of problems such as mixing of zinc and the like and clogging of the injector of the engine.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external perspective view of a fuel cooling device of the present invention, and FIG. 2 is a block diagram of a cooling system provided with the fuel cooling device. 3 is an exploded perspective view of the fuel cooling device of FIG. 1, FIG. 3a is a view showing the main body and the second closing body, and FIG. 3b is a view showing the first closing body. 4 is a view taken along arrows IV-IV in FIG. 3a, and FIG. 5 is a view taken along arrows VV in FIG. 3a. FIG. 6 is an exploded perspective view of another embodiment of the fuel cooling device, FIG. 6a is a view showing the device main body, and FIG. 6b is a view showing the first closing body.

  FIG. 1 shows the appearance of an embodiment of a fuel cooling device. This fuel cooling device 10 is formed by extruding a billet made of an aluminum alloy (Al-Mn alloy), and a device body 1 having a plurality of partition walls therein, and is formed on both ends of the device body 1 (not shown). The first and second closing bodies 2 and 3 for closing the opening are generally configured. The apparatus main body 1 has a cylindrical shape with a rectangular cross-sectional view including an upper side 11, a lateral side 12, 12 and a lower side (not shown), and a plurality of partition walls extending in the longitudinal direction are arranged at intervals in the inside. The end portions of the straight flow path defined by the partition walls are connected to each other to form a meandering flow path (described later).

  A plurality of radiating fins 15,... Extending in the longitudinal direction are formed on the upper side 11 of the apparatus main body 1. The radiating fins 15,... Are formed integrally with the apparatus main body 1 or bonded to the apparatus main body 1. Will be added later.

  The first closing body 2 includes a plate 21 and an inflow pipe 22 and an outflow pipe 23 protruding from one side thereof, and is formed of an aluminum alloy in the same manner as the apparatus main body 1. The inflow pipe 22 is connected to a return pipe (not shown) communicating with the internal combustion engine, and high-temperature return fuel returned from the internal combustion engine through the return pipe is taken into the fuel cooling device 10 through the inflow pipe 22. In the direction of arrow X1, the return fuel radiated through the meandering flow path in the fuel cooling device 10 flows out from the outflow pipe 23 and is returned to the fuel tank (in the direction of arrow X2).

  FIG. 2 is a block diagram illustrating a cooling system in which the fuel cooling device 10 is incorporated. This is a common rail system applied to a diesel engine, and fuel in a fuel tank 20 is sent to a common rail 50 for high-pressure fuel accumulation by a high-pressure pump 40 through a filter 30 for removing impurities in the fuel ( In the direction of arrow Y1, fuel is provided to each injector 60,. Each injector has its fuel injection timing and fuel injection amount adjusted by an engine control computer or the like, and injects fuel into the combustion chamber (in the direction of arrow Y2).

  Here, the high-temperature high-pressure fuel that is not injected is sent to the fuel cooling device 10 via the return pipe 70 (in the direction of arrow Y3), and the return fuel radiated in the fuel cooling device 10 is returned to the fuel tank 20 (in the direction of arrow Y4). ).

  FIG. 3 is an exploded perspective view of the fuel cooling device 10 shown in FIG. FIG. 3a shows the apparatus main body 1 and the second closing body 3, and the end side 13 of the apparatus main body 1 faces openings 13a,... Communicating with a straight flow path defined by partition walls 14,. Yes. On the end side 13, an endless protrusion 4 is formed at a position surrounding the entire opening 13 a.

  On the other hand, an endless recess 5 having a ring size slightly smaller than the ring size of the endless protrusion 4 communicates with the inflow pipe 22 on the surface facing the end side 13 of the first closing body 2 shown in FIG. Are formed outside both the inflow hole 22a and the outflow hole 23a communicating with the outflow pipe 23, and the endless protrusion 4 and the recess 5 are fitted to each other so that the apparatus main body 1 and the first closing body 2 are connected. It is assembled. In addition, when assembling both, the brazing material which consists of an Al-10% Si alloy is apply | coated to any one of the protrusion 4 and the groove 5 in advance.

  Also in the second closing body 3, an endless recess 5 is similarly formed on the side surface facing the end side of the apparatus main body 1, and is fitted to a not-shown protrusion provided on the end side. It has become so.

  FIG. 4 is a front view of the apparatus main body 1, as seen in the direction of arrows IV-IV in FIG. A sacrificial material (flux) made of a metal powder such as an Al-Zn alloy is coated on the outer surface of the fuel cooling device 10 for the purpose of improving corrosion resistance, and the sacrificial anticorrosive layer 6 is melted and diffused in a high temperature atmosphere. Is formed. Although FIG. 4 shows the apparatus main body 1, sacrificial anticorrosive layers are similarly formed on the outer surfaces of the first and second closing bodies 2 and 3.

  5 is a cross-sectional view taken along line VV in FIG. As shown in the figure, the meandering flow path Z is formed by staggering the end portions of the partition walls 14 in the partition walls 14,. The return fuel is radiated in the course of the return fuel flowing through the meandering flow path Z, and the temperature-returned return fuel is returned to the fuel tank.

  Here, an outline of a method for manufacturing the fuel cooling device 10 will be described. First, the apparatus main body 1, the 1st, 2nd obstruction | occlusion body 2 and 3 shown to FIG. In particular, the apparatus main body 1 is manufactured by extruding a billet made of an Al—Mn alloy. Next, a brazing material is applied to the endless ridges 4 formed on both end sides of the apparatus main body 1 and the endless ridges 4 and the recesses 5 are fitted to each other, whereby the apparatus main body 1 and the first and second closures are fitted. The bodies 2 and 3 are assembled. Next, the outer surface of the fuel cooling device 10 is coated with an Al—Zn alloy flux, and then the fuel cooling device 10 is placed in a high-temperature furnace in the melting temperature atmosphere of the brazing filler metal and the flux for a predetermined time. The device is manufactured by cooling.

  In the manufacturing process, the melted flux tries to enter the inside of the apparatus through the assembly surface of the apparatus main body 1 and the first and second closing bodies 2 and 3, but the end of the apparatus main body 1 is endless. The intrusion of flux is completely blocked by the formation of the protrusions.

  Further, since the apparatus main body 1 and the first and second closing bodies 2 and 3 are fitted together, a fixing jig for maintaining the assembly posture of both of them becomes unnecessary, and the fixing jig is used for fixing. The step of performing can be omitted.

  FIG. 6 shows another embodiment of the fuel cooling device. In this fuel cooling device, as shown in FIG. 6a, an endless recess 5A is formed on the end side of the device main body 1A, and the fuel cooling device is shown in FIG. 6b. Thus, the endless protrusion 4A is formed on the first closing body 2A. In addition, although illustration is abbreviate | omitted, an endless protrusion is similarly formed in a 2nd obstruction | occlusion body.

  According to the fuel cooling device of the present invention, the device main body and the closing bodies provided at both end sides thereof are assembled by fitting the endless protrusions and recesses provided respectively on the device main body and formed on the outer surface thereof. The aluminum alloy flux for the sacrificial anticorrosive layer is prevented from entering the inside thereof, so that the problem that the flux component Zn or the like is mixed with the return fuel and clogs the injector can be completely eliminated. . Further, the fuel cooling device of the present invention is obtained by adding a fitting structure of a main body and a closing body to a conventional cooling device, and does not increase the manufacturing cost.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

It is an external appearance perspective view of the fuel cooling device of the present invention. It is a block diagram of the cooling system provided with the fuel cooling device. FIG. 2 is an exploded perspective view of the fuel cooling device of FIG. 1, wherein (a) shows the device main body and a second closing body, and (b) shows the first closing body. It is the IV-IV arrow line view of FIG. 3a. It is the VV arrow line view of FIG. 3a. It is the disassembled perspective view of other embodiment of a fuel cooling device, (a) is an apparatus main body, (b) is the figure which showed the 1st obstruction | occlusion body, respectively.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1A ... Apparatus main body, 11 ... Upper side, 12 ... Lateral side, 13 ... End side, 13a ... Opening, 14 ... Partition, 15 ... Fin, 2, 2A ... 1st obstruction | occlusion body, 21 ... Plate, 22 ... Inflow Pipe, 22a ... Inflow hole, 23 ... Outflow pipe, 23a ... Outflow hole, 4, 4A ... Projection, 5, 5A ... Recess, 6 ... Sacrificial anticorrosion layer, 10 ... Fuel cooling device, Z ... Meandering flow path

Claims (4)

A fuel cooling device mounted on a vehicle,
A plurality of partition walls extending in the same direction inside the box are arranged at intervals, and a device body in which a meandering flow path is formed;
A first closing body and a second closing body for closing both ends of the apparatus main body,
One of the first closing body and the second closing body includes an inflow hole that communicates with the serpentine flow path and supplies return fuel flowing from the internal combustion engine to the serpentine flow path, and the serpentine flow path. In the fuel cooling device in which an outflow hole through which the return fuel that has flowed out flows out of the main body of the device is formed, and a sacrificial anticorrosive layer made of metal powder is formed on the outer surface thereof,
An endless ridge surrounding the end opening is formed on both end sides of the apparatus body facing the end opening communicating with the meandering flow path,
Of the first and second closing bodies, an endless recess is formed at a position corresponding to the protrusion on the side surface facing the end side of the apparatus main body,
A fuel cooling device characterized in that a protrusion and a recess are fitted together. A fuel cooling device mounted on a vehicle,
A plurality of partition walls extending in the same direction inside the box are arranged at intervals, and a device body in which a meandering flow path is formed;
A first closing body and a second closing body for closing both ends of the apparatus main body,
One of the first closing body and the second closing body includes an inflow hole that communicates with the serpentine flow path and supplies return fuel flowing from the internal combustion engine to the serpentine flow path, and the serpentine flow path. In the fuel cooling device in which an outflow hole through which the return fuel that has flowed out flows out of the main body of the device is formed, and a sacrificial anticorrosive layer made of metal powder is formed on the outer surface thereof,
On both end sides of the apparatus body facing the end opening communicating with the meandering flow path, endless concaves surrounding the end opening are formed,
Of the first and second closing bodies, endless ridges are formed at positions corresponding to the ridges on the side surfaces facing the end side of the apparatus main body,
A fuel cooling device characterized in that a recess and a protrusion are fitted together. A fuel cooling device mounted on a vehicle, wherein a plurality of partition walls extending in the same direction in a box are disposed at intervals and a meandering flow path is formed. An internal combustion engine comprising a first closing body and a second closing body that close both end sides, and one of the first closing body and the second closing body communicates with the meandering flow path. An inflow hole for supplying return fuel flowing in from the meandering flow path and an outflow hole for returning the return fuel flowing through the serpentine flow path out of the apparatus main body are formed. A method for manufacturing a fuel cooling device fitted to both end sides of an apparatus body,
Extruding the device main body, forming endless ridges surrounding the end opening on both end sides of the device main body facing the end opening communicating with the meandering flow path, and manufacturing the device main body; and The first and second closures are manufactured by forming endless recesses at positions corresponding to the protrusions on the side surfaces of the first and second closures facing the end of the apparatus body. And the process of
A second step of applying a brazing material to at least one of the concave stripes and the protrusions and fitting the both together, and assembling the first and second closures to both ends of the apparatus main body;
A method for manufacturing a fuel cooling device, comprising: a third step of coating a metal powder for forming a sacrificial anticorrosive layer on the outer surface of the fuel cooling device, and heat-treating the fuel cooling device. A fuel cooling device mounted on a vehicle, wherein a plurality of partition walls extending in the same direction in a box are disposed at intervals and a meandering flow path is formed. An internal combustion engine comprising a first closing body and a second closing body that close both end sides, and one of the first closing body and the second closing body communicates with the meandering flow path. An inflow hole for supplying return fuel flowing in from the meandering flow path and an outflow hole for returning the return fuel flowing through the serpentine flow path out of the apparatus main body are formed. A method for manufacturing a fuel cooling device fitted to both end sides of an apparatus body,
Extruding the device body, forming an endless recess surrounding the end opening on both end sides of the device body facing the end opening communicating with the meandering flow path, and manufacturing the device body; and The first and second closing bodies are manufactured by forming endless protrusions at positions corresponding to the concave stripes on the side surfaces of the first and second closing bodies facing the end side of the apparatus main body. And the process of
A second step of applying a brazing material to at least one of the concave stripes and the protrusions and fitting the both together, and assembling the first and second closures to both ends of the apparatus main body;
A method for manufacturing a fuel cooling device, comprising: a third step of coating a metal powder for forming a sacrificial anticorrosive layer on the outer surface of the fuel cooling device, and heat-treating the fuel cooling device.

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