JP2011094520A - Fuel delivery pipe provided with damper function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce dissonant noise radiated from the surface of an outer plate, in a fuel delivery pipe provided with a damper function to reduce a variation in the amount of fuel injected by deflecting the outer plate. <P>SOLUTION: A fuel delivery pipe body 10 forming a sealed internal space A filled with fuel supplied from a fuel pump and having predetermined pressure includes a bottom plate 11, a ceiling plate 12, front and rear plates 13, 14 and end plates 15 at both ends. The bottom plate is provided with a plurality of sockets 16 connected to a fuel injection valve. Plate-like composite material M with a soft thick foamed resin layer 20a and a bendable metallic thin plate 20b for backing up the foamed resin layer overlapped with and bonded to each other is bent to form a sound insulation cover 20 composed of the ceiling plate 12 and front and rear plates 13, 14. The sound insulating cover is closely mounted so that the surface of the foamed resin layer covers the main plate portions of the fuel delivery pipe body. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel delivery pipe for use in supplying fuel to an electronically controlled fuel injection engine.

  In this type of fuel delivery pipe, for example, as disclosed in Patent Document 1 below, an upper case (upper divided body) and a lower case (lower divided body) formed by pressing are integrally joined to form a lower portion. In some cases, a plurality of sockets (injector insertion recesses) to which a fuel injection valve (injector) is connected to a case are formed at a predetermined interval. This fuel delivery pipe is used by connecting a plurality of sockets provided in the lower case to each fuel injection valve of a multi-cylinder engine in a liquid-tight manner, and is supplied from the fuel pump through the fuel supply pipe into the fuel delivery pipe. The fuel of a predetermined pressure is supplied to the engine in an optimum amount according to the operating conditions by controlling the opening and closing of each fuel injection valve by the control unit. In such a fuel piping system including a fuel delivery pipe, when the fuel pressure inside the fuel delivery pipe fluctuates with the opening and closing of each fuel injection valve, the fuel injection amount varies and the air-fuel ratio can be kept within the target range. Although this is not possible, the problem is that the thickness of each plate part of the fuel delivery pipe is reduced, and each plate part is displaced in the plate thickness direction according to the change in the fuel pressure, and the volume of the internal space is changed to change the pressure fluctuation. It can be solved by mitigating. However, if the period of pressure fluctuation in the fuel delivery pipe caused by opening and closing of each fuel injection valve accompanying engine rotation approaches the natural vibration period of the fuel piping system, resonance will occur and the amplitude of fluctuation in pressure in the fuel delivery pipe will be Since it is amplified, the air-fuel ratio deviates greatly from the target range under such circumstances.

In Cited Document 1, since the plate thickness and shape are set so that the period of the resonance frequency of the fuel delivery pipe is less than the period of the idling speed, no resonance phenomenon occurs, and the pressure in the fuel delivery pipe does not occur. The amplitude of the fluctuation is not amplified. As a result, variations in the fuel injection amount due to variations in fuel pressure are reduced, so that the air-fuel ratio can be kept within the target range.
Japanese Patent No. 3538798 (paragraph [0005], paragraph [0011], paragraph [0031], FIGS. 3 and 4).

  In Patent Document 1 as described above, when the fuel pressure in the fuel delivery pipe fluctuates with the opening and closing of the fuel injection valve, the outer plate portion constituting the fuel delivery pipe is periodically bent. Sound waves are emitted from the surface of the outside. In addition, the outer plate part is flexibly shocked by the shock wave generated in the fuel delivery pipe as each fuel injection valve is opened and closed. Become. In addition, the fuel delivery pipe that reduces the fuel pressure fluctuation by changing the volume due to this internal pressure fluctuation needs to be thinned to some extent, so the temperature of the environment in which the engine is installed depends on the operating conditions. If the fuel pressure rises, the fuel in the fuel delivery pipe becomes hot and bubbles are generated, and the fuel injection amount becomes unstable, and there is a risk of causing heat damage such as variation in the air-fuel ratio. The object of the present invention is to solve each of these problems.

  To this end, a fuel delivery pipe having a damper function according to the first aspect of the present invention includes a bottom plate portion, a ceiling plate portion, a front plate portion, and a rear plate portion that are integrally connected to each other so as to form a cylindrical shape. The fuel injection valve is formed of an end plate portion that closes both ends of the fuel tank, and forms a sealed internal space filled with fuel of a predetermined pressure supplied from a fuel pump, and the bottom plate portion is opened and closed under the control of a control unit The fuel delivery pipe main body is provided with a plurality of sockets connected along the longitudinal direction, and each plate portion of the fuel delivery pipe main body is changed according to the fluctuation of the fuel pressure in the internal space due to the opening and closing of the fuel injection valve. A fuel device with a damper function that is displaced in the thickness direction to change the volume of the internal space, thereby reducing fluctuations in fuel pressure and reducing variations in fuel injection amount. In a varipipe, a plate-shaped composite material in which a flexible and thick foamed resin layer and a foldable metal thin plate that supports it are stacked and bonded together, the surface of the foamed resin layer is the ceiling plate part of the fuel delivery pipe body and the front and rear plate parts A horizontally long sound insulation cover that is bent into a shape consisting of an upper wall portion, a front wall portion, and a rear wall portion that are in contact with the outer surface of the fuel cell, and is attached so as to cover the fuel delivery pipe body. It is what.

  The fuel delivery pipe having the damper function according to claim 1, as in the invention according to claim 2, at least part of the ceiling plate portion and the front and rear plate portions connected to each other of the fuel delivery pipe main body, It is preferable to form a tube wall bent portion protruding inward along the longitudinal direction.

  In the fuel delivery pipe having the damper function according to claim 2, as in the invention according to claim 3, the sound insulation cover has an inner surface of the foamed resin layer of the sound insulation cover when attached to the fuel delivery pipe body. It is preferable to form a cover bent portion protruding inward at a position corresponding to the tube wall bent portion so as to be in contact with the outer surface of the tube wall bent portion.

  In the fuel delivery pipe having the damper function according to any one of claims 1 to 3, the sound insulation cover is preferably attached to the fuel delivery pipe body with an adhesive tape as in the invention according to claim 4.

  The fuel delivery pipe having a damper function according to any one of claims 1 to 3, wherein, as in the invention according to claim 5, the sound insulation cover is formed by fueling the inner surface of the foamed resin layer with a double-sided adhesive tape or an adhesive. It is preferably attached to the surface of the delivery pipe body.

  A fuel delivery pipe having a damper function according to claim 1 to claim 3, wherein the fuel delivery pipe is fixed to the lower surface of the bottom plate portion of the fuel delivery pipe main body and attached to the engine block as in the invention of claim 6. The sound insulation cover can be attached to and detached from the mounting bracket by a connecting member with each mounting piece extending forward and backward from the lower edge of the front wall portion and the rear wall portion contacting the upper surface of the mounting bracket. It is preferable to attach to a fuel delivery pipe main body by connecting to.

  The fuel delivery pipe having the damper function according to any one of claims 1 to 3 is fixed to the lower surface of the bottom plate portion of the fuel delivery pipe main body and is attached to the engine block as in the invention according to claim 7. The sound insulation cover is further extended outward from a position corresponding to a mounting hole on the lower edge of the front wall portion and the rear wall portion, and an insertion hole is provided at the tip portion thereof, respectively. The front and rear mounting pieces are formed, and the front end portions of the front and rear mounting pieces are superposed on the upper and lower sides of the mounting bracket so that the respective insertion holes substantially coincide with the center of the mounting hole, It is preferable that the fuel delivery pipe body is attached to the engine block with the insertion holes and the attachment bolts inserted into the attachment holes, and at the same time, the sound insulation cover is attached to the fuel delivery pipe body.

  The fuel delivery pipe having the damper function according to claim 7 is attached from the front wall portion to a part of the upper wall portion at a position corresponding to the mounting hole of the sound insulation cover, as in the invention according to claim 8. Form a notch to avoid interference with the mounting bolt that is inserted into the mounting hole of the bracket, and the front side mounting piece instead of extending from the lower edge of the front wall part, the upper wall that becomes the back part of the notch You may extend from the front edge of a part.

  The fuel delivery pipe having the damper function according to any one of claims 1 to 8, wherein the fuel delivery pipe body is integrally formed with a lower case made of a bottom plate as in the invention according to claim 9. It is preferable that the ceiling plate portion is composed of an upper case that is formed of a ceiling plate portion and front and rear plate portions and end plate portions that are liquid-tightly fixed to the upper side of the lower case to form an internal space with the lower case.

  9. The fuel delivery pipe having a damper function according to claim 1, wherein the fuel delivery pipe main body is a bottom plate portion and a ceiling plate portion that are integrally formed with each other as in the invention according to claim 10. Further, it is preferable to include a cylindrical portion formed of front and rear plate portions and a cap portion formed of an end plate portion that is liquid-tightly fixed so as to close both ends of the cylindrical portion to form an internal space.

  As described above, according to the first aspect of the present invention, a plate-like composite material in which a flexible and thick foamed resin layer and a foldable metal thin plate backing up the same are stacked and bonded together, and the surface of the foamed resin layer is a fuel delivery pipe. A horizontally long sound insulation cover that is bent into a shape consisting of an upper wall portion, a front wall portion, and a rear wall portion that are in contact with the outer surface of the ceiling plate portion of the main body and the front and rear plate portions, respectively, is provided. Since it is attached so as to cover the pipe body, in the thickness direction of the ceiling plate part of the fuel delivery pipe body due to pressure fluctuations and shock waves generated in the fuel delivery pipe body as the fuel injection valves open and close and the front and rear plate parts The generated periodic and shock vibrations are attenuated by contacting the foamed resin layer of the sound insulation cover backed up by the thin metal plate, and the pressure in the fuel delivery pipe body accompanying the engine rotation is reduced. Does not cause resonance even cycle of variation is consistent approaches to the period of natural vibration of the fuel pipe system or to this. Therefore, even in such a situation, since the amplitude of the pressure fluctuation in the fuel delivery pipe body is not amplified, the energy of the sound wave emitted from the fuel delivery pipe body is reduced and the emitted sound wave This energy is also absorbed by the sound insulation cover, and the annoying abnormal noise radiated to the outside is further reduced. Also, the plate thickness of the fuel delivery pipe body that bends due to fluctuations in the internal pressure needs to be reduced to some extent, but the fuel delivery pipe body is insulated by a sound insulation cover, so the engine may Even if the environmental temperature to be installed rises, the fuel in the fuel delivery pipe body does not immediately become high temperature accordingly, and there is no possibility of causing heat damage that causes variations in the air-fuel ratio.

  According to the invention of claim 2, a pipe wall bent portion protruding inward along the longitudinal direction is formed on at least a part of the ceiling plate portion and the front and rear plate portions connected to each other of the fuel delivery pipe body. At the wall bend, the displacement in the plate thickness direction is increased and the volume fluctuation of the fuel delivery pipe body is also increased. Therefore, the pressure fluctuation caused by opening and closing of the fuel injection valve is greatly absorbed and greatly reduced. Variations in the fuel injection amount due to fluctuations in the air-fuel ratio are reduced and the air-fuel ratio is improved. As a result, the periodic and impact bending of the ceiling plate portion and the front and rear plate portions, particularly the bent portion of the tube wall increases, so that the energy of the sound wave emitted from these portions increases. Since the sound wave energy from the sound wave is absorbed by the sound insulation cover, an increase in annoying abnormal noise radiated to the outside is considerably suppressed.

  The sound insulation cover protrudes inward at a position corresponding to the bent portion of the tube wall so that the inner surface of the foamed resin layer of the sound insulation cover contacts the outer surface of the bent portion of the tube wall when attached to the fuel delivery pipe body. According to the invention of claim 3 in which the cover bent portion is formed, the inner surface of the foamed resin layer of the sound insulating cover abuts on the outer surface of the tube wall bent portion due to the vibration caused by the periodic and impact bending generated in the tube wall bent portion. Therefore, the energy of the sound wave radiated from the tube wall bend is reduced, and thus the energy of the sound wave radiated from the bend of the tube wall is reduced as described above. As described above, the sound-insulating cover absorbs the harsh noise that is radiated to the outside.

  According to the invention of claim 4 in which the sound insulation cover is attached to the fuel delivery pipe main body with an adhesive tape, it is very easy to attach the sound insulation cover to the fuel delivery pipe without adding a special structure to the fuel delivery pipe main body and the sound insulation cover. Can be attached to the body.

  According to the invention of claim 5, the inner surface of the foamed resin layer is attached to the surface of the fuel delivery pipe main body with a double-sided adhesive tape or an adhesive, as in the invention of claim 4. The sound insulation cover can be attached to the fuel delivery pipe body very easily without adding any special structure to the cover.

  It further includes a mounting bracket fixed to the lower surface of the bottom plate of the fuel delivery pipe body and formed with a mounting hole for the engine block, and the sound insulation cover extends from the lower edge of the front wall portion and the rear wall portion to the front and rear. According to the invention of claim 6, the sound insulation cover is attached to and detached from the fuel delivery pipe body by bringing the piece into contact with the upper surface of the mounting bracket and detachably connecting to the mounting bracket by the connecting member. It can be done arbitrarily and easily.

  It further includes a mounting bracket that is fixed to the lower surface of the bottom plate portion of the fuel delivery pipe body to form a mounting hole for the engine block, and the sound insulation cover corresponds to the mounting hole on the lower edge of the front wall portion and the rear wall portion. Front and rear mounting pieces that are respectively extended outward from the positions and provided with insertion holes at the tip portions are formed, and the tip portions of the front and rear mounting pieces are placed on the upper and lower sides of the mounting bracket. Each of the insertion holes are overlapped so that they coincide with the center of the mounting hole, and the fuel delivery pipe body is attached to the engine block with the mounting bolts inserted into the insertion holes and the mounting holes, and at the same time, the sound insulation cover is attached to the fuel delivery pipe body. According to the seventh aspect of the invention, the sound insulation cover can be attached to and detached from the fuel delivery pipe body simply by adding the front and rear attachment pieces to the sound insulation cover. It is possible.

  At the position corresponding to the mounting hole of the sound insulation cover, a notch is formed from the front wall part to a part of the upper wall part to avoid interference with the mounting bolt inserted through the mounting hole of the mounting bracket. Instead of extending from the lower edge of the front wall portion, the protruding amount of the mounting bolt from the sound insulation cover is extended from the front edge of the upper wall portion which is the back portion of the notch. Since it can be reduced, the space required for mounting the fuel delivery pipe can be reduced.

  A fuel having a damper function in which the volume of the internal space is changed by displacing each plate portion of the fuel delivery pipe body in the plate thickness direction in accordance with the change in the fuel pressure in the internal space due to the opening and closing of the fuel injection valve In the delivery pipe, it is necessary to reduce the plate thickness of the fuel delivery pipe body, but the fuel delivery pipe body is composed of a lower case made of a bottom plate portion, a ceiling plate portion formed integrally with each other, and front and rear plate portions. According to the invention of claim 9, which is composed of an end plate portion and is liquid-tightly fixed on the upper side of the lower case and forms an internal space with the lower case, the thin fuel delivery pipe body is made high. Can be manufactured with productivity.

  The fuel delivery pipe body is formed in a liquid-tight manner so as to close both ends of the cylindrical portion and the cylindrical portion composed of a bottom plate portion, a ceiling plate portion, and front and rear plate portions formed integrally with each other to form an internal space. According to the invention of claim 10 comprising the cap portion comprising the end plate portion, the thin fuel delivery pipe main body can be manufactured at low cost even when the production amount is small.

It is the top view which fractured | ruptured a part of 1st Embodiment of the fuel delivery pipe provided with the damper function by this invention. It is the front view which fractured | ruptured a part of 1st Embodiment shown in FIG. FIG. 3 is a 3-3 cross-sectional view of FIG. 1. FIG. 4 is a sectional view taken along the line 4-4 in FIG. 1. It is the top view which fractured | ruptured one part except the intermediate part of 2nd Embodiment of the fuel delivery pipe provided with the damper function by this invention. It is the front view which fractured | ruptured a part of right half part of 2nd Embodiment shown in FIG. FIG. 7 is a sectional view taken along line 7-7 in FIG. It is 8-8 sectional drawing of FIG. It is a top view of the right half part of 3rd Embodiment of the fuel delivery pipe provided with the damper function by this invention. FIG. 10 is a sectional view taken along the line 10-10 in FIG. 9;

  First, a first embodiment of a fuel delivery pipe having a damper function according to the present invention will be described with reference to FIGS. The first embodiment includes a fuel delivery pipe main body 10 including a horizontally long lower case 10b integrally formed with a plurality of sockets 16 and a horizontally long upper case 10c that is brazed and fixed so as to cover the entire upper side thereof. Two mounting brackets 18 that are brazed and fixed to the lower surface of the lower case 10b, a fuel supply pipe 17 that is brazed and fixed to the left end surface of the upper case 10c, and a horizontally-long soundproof cover 20 that covers the fuel delivery pipe body 10. It is comprised by. Each member 10b, 10c, 17, 18 is made of a steel material and is plated with nickel in advance for rust prevention.

  As shown in FIGS. 1 to 4, the lower case 10 b includes an elongated bottom plate portion 11 having a flange portion 11 a having a constant height formed on the entire circumference, and is integrally formed by sheet metal pressing. Four bottomed cylindrical sockets 16 projecting upward are integrally formed on the bottom plate portion 11 at regular intervals along the longitudinal direction, and the interior of the socket 16 is placed on the upper case 10c in the upper case 10c. An opening 16a communicating with the internal space A is formed. A fuel supply part of the fuel injection valve is liquid-tightly connected to each socket 16 from below. The mounting bracket 18 of the first embodiment has a two-step cross-sectional shape, one of which is brazed to the lower surface of the lower case 10b, and the other step is a fuel delivery pipe body. An attachment hole 18a for attaching 10 to the engine block is formed. At the front edge of the bottom plate portion 11 including the flange portion 11a, bottom plate recessed portions 11b are formed at both ends corresponding to the mounting holes 18a of the mounting bracket 18 to avoid interference with mounting bolts to the engine block described later. ing. The front side of the fuel delivery pipe according to the present invention refers to the side where the mounting hole 18a of the mounting bracket 18 is provided.

  As shown in FIGS. 1 to 4, the upper case 10 c includes a ceiling plate portion 12, a front plate portion 13 and a rear plate portion 14 that extend downward from front and rear edges thereof, and both end portions of these plate portions 12 to 14. It consists of the end plate part 15 to be closed, and is integrally formed by sheet metal pressing. The ceiling plate portion 12 is formed with a tube wall bent portion 10a protruding inward along most of the longitudinal direction excluding both end portions. In the front plate portion 13 and the tube wall bent portion 10a of the upper case 10c, two upper recessed portions 13a having a shape in which the inner side of the lower portion substantially contacts the outside of the flange portion 11a of the bottom plate recessed portion 11b of the bottom plate portion 11 are provided. Is formed. The tube wall bent portion 10a is located between the two upper recessed portions 13a. Small inward projections 10c1 are formed at a plurality of locations below the plate portions 13 and 14 on the front and rear sides of the upper case 10c.

  The upper case 10c is fitted with the front and rear plate portions 13 and 14 and the lower inner portions of the end plate portions 15 on the inner sides of the flange portion 11a of the bottom plate portion 11 on the outer periphery of the flange portion 11a with a slight gap. Then, the entire upper side of the lower case 10b is covered, and the inward projection 10c1 is positioned in contact with the upper edge of the longitudinal flange portion 11b, and is liquid-tightly brazed and fixed between the lower case 10b and the upper case 10c. A fuel delivery pipe body 10 having an internal space A filled with fuel is formed. The fuel delivery pipe main body 10 thus configured includes a bottom plate portion 11, a ceiling plate portion 12, a front plate portion 13 and a rear plate portion 14 that are integrally connected to each other so as to be cylindrical in a completed state. It consists of an end plate portion 15 that closes both ends, and a sealed space A is formed inside. One end of the fuel supply pipe 17 is inserted into the flanged opening 15a formed by burring in the end plate portion 15 on the left side of the fuel delivery pipe main body 10, and is fixed in a liquid-tight manner by brazing. The total length of the fuel delivery pipe main body 10 is 299.5 mm, for example, and the plate thickness of each of the plate portions 11 to 15 is 1.0 mm or 1.2 mm, for example.

  As shown in FIGS. 1 to 4, the sound insulating cover 20 is formed by stacking and bonding a flexible and thick foamed resin layer 20 a having vibration damping and sound absorbing functions and a foldable metal thin plate 20 b serving as a backup material for maintaining the shape. The plate-like composite material M is of a horizontally long shape that is folded into a channel shape having a U-shaped cross section composed of the upper wall portion 21, the front wall portion 22, and the rear wall portion 23 so that the foamed resin layer 20a is on the inner side. . The sound insulation cover 20 covers the outside of the upper case 10c of the fuel delivery pipe main body 10 except for both ends, and the inner surface of the foamed resin layer 20a of each wall 21 to 23 has a considerable fastening allowance. The fuel delivery pipe main body 10 is composed of a main adhesive tape 30a provided at the central portion in the longitudinal direction and an auxiliary adhesive tape 30b provided at both ends so as to be in close contact with the ceiling plate portion 12 and the front and rear plate portions 13 and 14 of the upper case 10c. Attached to. The pressure-sensitive adhesive tapes 30a and 30b are obtained by applying a sticky adhesive to one side of a tape base material made of an aluminum foil. The foamed resin layer 20a is an ethylene propylene rubber sponge material having a thickness of 3 mm, for example, and the metal thin plate 20b is an aluminum plate material having a thickness of 0.3 mm, for example.

  A pair of sound insulation covers 20 corresponding to the upper recessed portion 13a of the upper case 10c is provided on both ends of the sound insulation cover 20 from the front wall portion 22 to the upper wall portion 21 in order to avoid interference with a mounting bolt to an engine block described later. The notch 24 is formed. The sound insulation cover 20 between the notches 24 is formed with a cover bent portion 20c protruding inward along most of the longitudinal direction corresponding to the tube wall bent portion 10a of the upper case 10c. The inner surface of the foamed resin layer 20a of the bent portion 20c is in contact with the outer surface of the tube wall bent portion 10a of the upper case 10c with a considerable tightening margin.

  In the fuel delivery pipe having the damper function according to the first embodiment, the fuel supply portions of the fuel injection valves attached to the engine are liquid-tightly connected to the four sockets 16 formed in the bottom plate portion 11. In the state, it is attached to the engine block 34 by a mounting bolt inserted through the mounting hole 18a of the mounting bracket 18. In this state, fuel of a predetermined pressure supplied from a fuel pump (not shown) through the fuel supply pipe 17 is filled in the internal space A of the fuel delivery pipe body 10, and is supplied from each fuel injection valve controlled to be opened and closed by the control unit. It is injected into the engine.

  During this operation, the periodicity of the ceiling plate portion 12 of the upper case 10c and the front and rear plate portions 13 and 14 generated by pressure fluctuations and shock waves generated in the fuel delivery pipe main body 10 with the opening and closing of the fuel injection valves. The vibration due to the impact deflection is attenuated by contacting the inner surface of the foamed resin layer 20a of the sound insulation cover 20, and the period of pressure fluctuation in the fuel delivery pipe body accompanying the engine rotation becomes the period of natural vibration of the fuel piping system. When approaching or coincides with it, there is no resonance and the amplitude of pressure fluctuations in the fuel delivery pipe body is not amplified. Accordingly, even in such a state, the energy of sound waves emitted from the fuel delivery pipe body 10 is reduced, the energy of sound waves emitted from them is reduced, and the energy of the emitted sound waves is also reduced by the sound insulation cover 20. The annoying noise that is absorbed and radiated to the outside is further reduced.

  Further, the thickness of the plate portion of the fuel delivery pipe body which is bent due to fluctuations in the internal pressure needs to be reduced to some extent. However, since the fuel delivery pipe body 10 is insulated by the sound insulation cover 20, the engine may be affected by operating conditions. Even if the environmental temperature to be installed rises, the fuel in the fuel delivery pipe body does not immediately become high temperature accordingly, and there is no possibility of causing heat damage that causes variations in the air-fuel ratio.

  Further, the sound insulating cover 20 adjusts the shape of the foldable metal thin plate 20b that backs up the foamed resin layer 20a, so that the foamed resin layer 20a on the ceiling plate 12 and the front and rear plate parts 13 and 14 of the upper case 10c. By adjusting the tightening allowance, it is possible to adjust the pressing force on each of the plate portions 12 to 15 so as to obtain a necessary damping effect. Further, since the sound insulation cover 20 has a flat outer surface by the metal thin plate 20b, the appearance of the fuel delivery pipe having a damper function including the sound insulation cover 20 can be improved.

  In the first embodiment described above, the tube wall bent portion 10a that protrudes inward along the longitudinal direction is formed on the ceiling plate portion 12 of the upper case 10c of the fuel delivery pipe body 10 and a part of the front and rear plate portions 13 and 14. In such a tube wall bent portion 10a, the displacement rigidity decreases in the plate thickness direction, and the volume variation with respect to the pressure variation of the fuel delivery pipe main body 10 increases, thereby opening and closing the fuel injection valve. Since the ability to absorb the generated pressure fluctuation is also increased, the variation of the fuel injection amount due to the fluctuation of the fuel pressure is reduced and the air-fuel ratio is improved. Along with this, the periodic and impact bending of the ceiling plate portion 12 and the front and rear plate portions 13 and 14, particularly the tube wall bent portion 10 a increases, so that the energy of sound waves emitted from these portions increases. Since the sound wave energy radiated from these portions is absorbed by the sound insulation cover 20, an increase in annoying abnormal noise radiated to the outside is suppressed to a considerable extent.

  In addition to this, in the first embodiment described above, the inner surface of the foamed resin layer 20a of the sound insulating cover 20 is inward so that the inner surface of the sound insulating cover 20 is in contact with the outer surface of the tube wall bent portion 10a when attached to the fuel delivery pipe body 10. The cover bent portion 20c is formed so as to protrude, and the vibration caused by the periodic and impact bending of the tube wall bent portion 10a is attenuated by the foamed resin layer 20a of the cover bent portion 20c to be contacted. The sonic energy is reduced, and the sonic energy is further absorbed by the foamed resin layer 20a of the cover bent portion 20c, so that annoying abnormal noise radiated to the outside is further suppressed.

  In the first embodiment described above, the sound insulation cover 20 is attached to the fuel delivery pipe main body 10 by the adhesive tapes 30a and 30b. In this way, a special structure is added to the fuel delivery pipe main body 10 and the sound insulation cover 20. Without this, the sound insulation cover 20 can be attached to the fuel delivery pipe body 10 very easily. Instead of attaching the sound insulation cover 20 to the fuel delivery pipe body 10 with the adhesive tapes 30a and 30b as described above, the inner surfaces of the foamed resin layers 20a of the wall portions 21 to 23 of the sound insulation cover 20 are attached to the fuel delivery with a double-sided adhesive tape. You may attach so that it may contact | adhere to the surface of the pipe main body 10, or you may adhere the inner surface of each foamed resin layer 20a of each wall part 21-23 of the sound insulation cover 20 to the surface of the fuel delivery pipe main body 10 with an adhesive agent. You may adhere to. The mounting bolt that is inserted into the mounting hole 18a of the mounting bracket 18 and attaches the fuel delivery pipe to the engine block is mostly located in the upper recessed portion 13a of the upper case 10c and is positioned from the fuel delivery pipe body 10 and the sound insulation cover 20. Since the protrusion amount is reduced, the space required for mounting the fuel delivery pipe can be reduced.

  Further, in the first embodiment described above, the fuel delivery pipe main body 10 includes a lower case 10b composed of a bottom plate portion 11, a ceiling plate portion 12 formed integrally with each other, front and rear plate portions 13, 14 and end plate portions. 15 and is composed of an upper case 10c that is liquid-tightly fixed to the upper side of the lower case 10b and forms an internal space A between the lower case 10b. Both the lower case 10b and the upper case 10c are formed. Since it can be easily formed by sheet metal pressing, and the liquid-tight fixation of the lower case 10b and the upper case 10c can be easily performed by brazing, the thin-walled fuel delivery pipe body 10 can be manufactured with high productivity. .

  Next, a second embodiment of a fuel delivery pipe having a damper function according to the present invention will be described with reference to FIGS. In the second embodiment, a fuel delivery pipe main body 10 including an integrally formed square cylindrical portion 10d and a cap portion 10e fixed in a liquid-tight manner so as to close both ends thereof, and a lower surface of the cylindrical portion 10d. A plurality of sockets 16 fixed by brazing and two mounting brackets 18, a fuel supply pipe 17 fixed by brazing to the left cap portion 10 e, and a sound insulation cover 20 that covers the fuel delivery pipe body 10 in close contact with each other. Has been. As in the first embodiment, the members 10d, 10e, 17, and 18 are made of steel and are plated with nickel in advance for rust prevention.

  As shown in FIGS. 5 to 7, the cylindrical portion 10 d is a thin steel pipe having a substantially square cross-sectional shape including a bottom plate portion 11, a ceiling plate portion 12, and front and rear plate portions 13 and 14 formed integrally with each other. Is cut. The cap portion 10e has a substantially square shape with a flange portion of a certain length formed on the entire circumference. The cap portion 10e is fitted to the inner surfaces of both ends of the cylindrical portion 10d and is liquid-tightly brazed and fixed to form the internal space A. As shown in FIGS. 5 and 6, the socket 16 is a separate molded product comprising a bottomed cylindrical main body portion 16b and a cylindrical portion 16c having a smaller diameter than the main body portion 16b protruding outward from the upper bottom surface thereof. is there. The socket 16 has a cylindrical portion 16c inserted from below into a mounting hole 11d formed at equal intervals along the longitudinal direction in the bottom plate portion 11 of the cylindrical portion 10d, and the bottom surface of the main body portion 16b is connected to the bottom surface of the bottom plate portion 11. And brazed to the cylindrical portion 10d. The inside of the main body portion 16b of the socket 16 thus fixed is communicated with the internal space A of the fuel delivery pipe main body 10 through the opening 16a formed by the inner surface of the opening 16a.

  Unlike the first embodiment, the fuel delivery pipe main body 10 of the second embodiment is not provided with a bottom plate and front concave portions corresponding to the upper concave portions 11b and 13a. Each mounting bracket 18 that is brazed and fixed to the lower surface of the fuel delivery pipe body 10 has a flat plate shape with mounting holes 18a through which mounting bolts to the engine block are passed. As shown in FIGS. 5 and 7, each mounting bracket 18 is formed with mounting protrusions 18 b and 18 c protruding forward and backward from the bottom plate portion 11 on one side edge which is the inner side in the longitudinal direction of the fuel delivery pipe body 10. The mounting projections 18b and 18c are formed with cover mounting holes 18d for mounting the sound insulation cover 20 described below.

  As in the first embodiment, the sound-insulating cover 20 is made of a plate-shaped composite material M made of a foamed resin layer 20a and a thin metal plate 20b, and a channel having a U-shaped cross section made of an upper wall portion 21, a front wall portion 22 and a rear wall portion 23. Although it is a horizontally long shape bent into a shape, no recess is provided on the front side of the fuel delivery pipe main body 10, and therefore no corresponding notch is provided. The sound insulation cover 20 is formed with attachment pieces 25 extending in the front-rear direction from the lower edge of the front wall portion 22 and the lower edge of the rear wall portion 23 at positions corresponding to the attachment protrusions 18b and 18c. The piece 25 is formed with an insertion hole 25a having the same diameter as the mounting protrusion 18c. As in the first embodiment, the sound insulating cover 20 has the inner surface of the foamed resin layer 20a of each of the walls 21 to 23 with a considerable tightening margin, and the ceiling plate 12 of the upper case 10c of the fuel delivery pipe body 10 and the front and rear The outer sides of the upper case 10c of the fuel delivery pipe body 10 are closely contacted and covered so as to be in contact with the plate portions 13 and 14, and the respective mounting pieces 25 are brought into contact with the upper surfaces of the respective mounting projections 18b and 18c. The connecting member 31 is inserted into the fuel delivery pipe main body 10 by bringing them into contact with each other and aligning the insertion holes 25a of the mounting pieces 25 and the cover mounting holes 18d.

  The connecting member 31 is a molded product made of a synthetic resin (for example, polyacetal resin, polyamide resin, etc.) having high strength and high elasticity. As shown mainly in FIGS. 7 and 8, the hollow cylindrical shaft portion 31a and one end thereof are formed. Is formed with a rectangular head 31b formed integrally with each other, and a triangular engagement protrusion 31c with a pointed tip is provided at two locations opposite to each other in the circumferential direction of the half of the shaft 31a. The shaft 31a is formed integrally with a slit 31d that passes through both sides of each engaging projection 31c and is connected to the head 31b. The slit 31d reaches the inner surface of the hollow shaft portion 31a, so that the wide portion of the engagement protrusion 31c on the head portion 31b side can elastically appear and disappear in the shaft portion 31a.

  As described above, the fuel delivery pipe main body 10 is covered with the sound insulation cover 20, and the mounting pieces 25 are brought into contact with the upper surfaces of the mounting protrusions 18b and 18c. Then, if each insertion hole 25a and each cover mounting hole 18d are aligned and the connecting member 31 is inserted, as shown in FIG. 8, the engaging protrusion 31c is bent into the shaft portion 31a, and the connecting member 31 has the head portion 31b. The fitting piece 25 is inserted to a position where it abuts on the thin metal plate 20b, and each engagement protrusion 31c passes through the cover attachment hole 18d of the attachment protrusion 18c and is elastically restored, and the connecting member 31 is covered with the cover attachment hole 18d of the attachment protrusion 18c. The sound insulation cover 20 is attached to the mounting bracket 18 so that the inner surface of the foamed resin layer 20a is in close contact with the ceiling plate portion 12 and the front and rear plate portions 13 and 14 of the upper case 10c of the fuel delivery pipe body 10. It is done. According to such a connecting member 31, the mounting of the sound insulation cover 20 to the mounting bracket 18 is very simple. However, the present invention is not limited to this, and the cover mounting hole 18d of the mounting bracket 18 is a screw hole. It is also possible to attach the connecting member 31 as a machine screw.

  Also in the second embodiment, as in the first embodiment, the periodicity and impact of the ceiling plate portion 12 of the upper case 10c and the front and rear plate portions 13 and 14 caused by pressure fluctuations and shock waves generated in the fuel delivery pipe main body 10 are similar. Vibration due to mechanical deflection is attenuated by contacting the inner surface of the foamed resin layer 20a of the sound insulation cover 20, and the period of pressure fluctuation in the fuel delivery pipe body approaches or is close to the period of natural vibration of the fuel piping system. Even if they coincide, resonance does not occur. Therefore, even in such a state, the annoying abnormal noise radiated to the outside is reduced. In addition, since the fuel delivery pipe body 10 is insulated by the sound insulation cover 20, even if the environmental temperature at which the engine is installed increases due to operating conditions or the like, there is a risk of causing heat damage that causes variations in the air-fuel ratio. Absent. Also in this second embodiment, it is possible to adjust the pressing force against each plate portion 12-15 so as to obtain the necessary damping effect by adjusting the tightening margin of the foamed resin layer 20a with respect to the upper case 10c. The appearance can be improved by the metal thin plate 20b. In this second embodiment, the pipe wall bent portion is not provided in the fuel delivery pipe main body 10, but it is possible to provide the pipe wall bent portion, and in this way, the effect of the pipe wall bent portion as described above can be obtained. It can also be obtained.

  In the second embodiment, the sound insulation cover 20 is attached by the connecting member 31 with the attachment pieces 25 extending forward and backward from the lower edges of the front wall portion 22 and the rear wall portion 23 in contact with the upper surface of the attachment bracket 18. Since it is attached to the fuel delivery pipe body 10 by being detachably connected to the bracket 18, the sound insulation cover 20 can be attached to and detached from the fuel delivery pipe body 10 arbitrarily and easily.

  In the second embodiment, since the fuel delivery pipe main body 10 is composed of a cylindrical portion 10d obtained by cutting a thin steel pipe and a small cap portion 10e, the thin fuel delivery pipe main body 10 when the production amount is small can be obtained at low cost. Can be manufactured.

  Next, a third embodiment of a fuel delivery pipe having a damper function according to the present invention will be described with reference to FIGS. In the third embodiment, the fuel delivery pipe main body 10 including the fuel supply pipe 17 and the mounting bracket 18 is substantially the same as the first embodiment described above, and the mounting portion of the sound insulation cover 20 with respect to the fuel delivery pipe main body 10 is the same. Since only the structure is different from the first embodiment, this difference will be mainly described.

  As in the first embodiment, the sound insulation cover 20 has a horizontally long shape bent into a channel shape having a U-shaped cross section composed of an upper wall portion 21 and front and rear wall portions 22 and 23, and a foamed resin layer on each wall portion 21 to 23. The inner surface of 20a is brought into contact with the ceiling plate portion 12 and the front and rear plate portions 13 and 14 of the fuel delivery pipe body 10 with a considerable tightening margin, and a notch 24 is also provided. The sound insulating cover 20 is located at a position corresponding to the mounting hole 18a of the mounting bracket 18 in a state where the fuel delivery pipe main body 10 is covered, and forwardly from the front edge of the upper wall portion 21 which is the back portion of the notch 24. A front mounting piece 26 having an insertion hole 26a formed at the tip is provided to extend, and is similarly inserted outwardly from the lower edge of the rear wall 23 at a position corresponding to the mounting hole 18a of the mounting bracket 18. A rear attachment piece 27 in which the hole 27a is formed is provided so as to extend.

  The sound insulation cover 20 of the third embodiment is similar to the first embodiment in that the ceiling surface of the upper case 10c of the fuel delivery pipe main body 10 with the inner surface of the foamed resin layer 20a of each of the walls 21 to 23 having a considerable tightening allowance. Cover the outer side of the upper case 10c of the fuel delivery pipe body 10 so as to be in contact with the portion 12 and the front and rear plate portions 13 and 14, and cover the front ends of the front and rear mounting pieces 26 and 27. The mounting bolts 32 are superposed on the upper and lower sides of the mounting bracket 18 so that the respective insertion holes 26a and 37a substantially coincide with the center of the mounting hole 18a, and the mounting bolts 32 inserted into the respective insertion holes 26a and 27a and the mounting hole 18a are provided. And screwed into the engine block 34 via the spacer 33. Thereby, the sound insulation cover 20 is attached to the fuel delivery pipe body 10 at the same time as the fuel delivery pipe body 10 is attached to the engine block 34.

  According to the third embodiment, the sound insulation cover 20 can be arbitrarily attached to and detached from the fuel delivery pipe body 10 simply by adding the front and rear attachment pieces 26 and 27 to the sound insulation cover 20. Other configurations and operational effects of the third embodiment are the same as those of the first embodiment described above, and thus further description thereof is omitted.

  In the third embodiment, the mounting bolt 32 that is inserted into the mounting hole 18a of the mounting bracket 18 and the insertion holes 26a, 27a of the front and rear mounting pieces 26, 27 and attaches the fuel delivery pipe body 10 to the engine block 34, Since most of the fuel delivery pipe body 10 is located in the recesses 11b and 13a of the fuel delivery pipe body 10 and the amount of protrusion from the fuel delivery pipe body 10 and the sound insulation cover 20 is reduced, the space required for mounting the fuel delivery pipe can be reduced. it can. However, the third embodiment is not limited to this, and it is also possible to apply the present embodiment to the front portion of the fuel delivery pipe main body 10 and the sound insulation cover 20 not having a notch as in the second embodiment. In that case, the front and rear attachment pieces 26, 27 may be provided so as to extend outward from the lower edges of the front wall portion 22 and the rear wall portion 23 of the sound insulating cover 20.

DESCRIPTION OF SYMBOLS 10 ... Fuel delivery pipe main body, 10a ... Pipe wall bending part, 10b ... Lower case, 10c ... Upper case, 10d ... Cylindrical part, 10e ... Cap part, 11 ... Bottom board part, 12 ... Ceiling board part, 13 ... Front board part , 14 ... rear plate portion, 15 ... end plate portion, 16 ... socket, 18 ... mounting bracket, 18a ... mounting hole, 20 ... sound insulation cover, 20a ... foamed resin layer, 20b ... thin metal plate, 20c ... cover bent portion, 21 ... upper wall part, 22 ... front wall part, 23 ... rear wall part, 24 ... notch, 25 ... mounting piece, 25a ... insertion hole, 26 ... front side mounting piece, 26a ... insertion hole, 27 ... rear side mounting piece, 27a ... Insertion hole, 30a, 30b ... Adhesive tape, 31 ... Connecting member, 32 ... Mounting bolt, 34 ... Engine block, A ... Internal space, M ... Plate-shaped composite material.

Claims (10)

A bottom plate, a ceiling plate, a front plate and a rear plate that are integrally connected to each other so as to form a cylinder, and an end plate that closes both ends thereof, and fuel of a predetermined pressure supplied from a fuel pump A fuel delivery pipe having a plurality of sockets along the longitudinal direction, which form a sealed internal space filled with fuel and are connected to a fuel injection valve controlled by a control unit to be opened and closed. Comprising a main body, and changing the volume of the internal space by displacing each plate portion of the fuel delivery pipe main body in the plate thickness direction according to a change in fuel pressure in the internal space due to opening and closing of the fuel injection valve, In the fuel delivery pipe with a damper function that reduces the variation in the fuel injection amount by reducing the fluctuation of the fuel pressure,
A plate-shaped composite material in which a flexible and thick foamed resin layer and a foldable metal thin plate that supports it are stacked and bonded together, and the surface of the foamed resin layer is formed between the ceiling plate portion of the fuel delivery pipe body and the front and rear plate portions. It has a horizontally long sound insulation cover that is bent into a shape consisting of an upper wall portion, a front wall portion, and a rear wall portion that are in contact with the outer surface,
A fuel delivery pipe having a damper function, wherein the sound insulation cover is attached so as to cover the fuel delivery pipe body.   2. A fuel delivery pipe having a damper function according to claim 1, wherein at least a part of the ceiling plate portion and the front and rear plate portions of the fuel delivery pipe main body that are connected to each other protrude inward along the longitudinal direction. A fuel delivery pipe having a damper function, characterized in that a bent portion of the pipe wall is formed.   3. The fuel delivery pipe having a damper function according to claim 2, wherein an inner surface of the foamed resin layer of the sound insulation cover is in contact with an outer surface of the pipe wall bent portion when attached to the fuel delivery pipe body. A fuel delivery pipe having a damper function, wherein a cover bent portion projecting inwardly is formed at a position corresponding to the tube wall bent portion so as to be in contact therewith.   The fuel delivery pipe having a damper function according to any one of claims 1 to 3, wherein the sound insulation cover has a damper function attached to the fuel delivery pipe body by an adhesive tape. Fuel delivery pipe.   The fuel delivery pipe having a damper function according to any one of claims 1 to 3, wherein the sound insulation cover has an inner surface of a foamed resin layer of the fuel delivery pipe body using a double-sided adhesive tape or an adhesive. A fuel delivery pipe with a damper function characterized by being attached to the surface.   The fuel delivery pipe having the damper function according to any one of claims 1 to 3, wherein the fuel delivery pipe is fixed to a lower surface of a bottom plate portion of the fuel delivery pipe body, and an attachment hole to the engine block is formed. The sound insulation cover further includes a bracket, and each mounting piece extending forward and backward from the lower edge of the front wall portion and the rear wall portion is brought into contact with the upper surface of the mounting bracket, and can be attached to and detached from the mounting bracket by a connecting member. A fuel delivery pipe having a damper function, wherein the fuel delivery pipe is attached to the main body of the fuel delivery pipe by being connected.   The fuel delivery pipe having the damper function according to any one of claims 1 to 3, wherein the fuel delivery pipe is fixed to a lower surface of a bottom plate portion of the fuel delivery pipe body, and an attachment hole to the engine block is formed. The soundproof cover further includes a bracket, and the sound insulation cover has a front side that extends outward from a position corresponding to the mounting hole on the lower edge of the front wall portion and the rear wall portion, and is provided with an insertion hole at the tip portion, respectively. And the rear mounting pieces are formed, and the front end portions of the front and rear mounting pieces are superposed on the upper and lower sides of the mounting bracket so that their insertion holes are substantially coincident with the center of the mounting holes. The fuel delivery pipe main body is attached to the engine block by the insertion holes and the mounting bolts inserted through the mounting holes, and at the same time, the sound insulation cover is attached to the fuel delivery pipe main body. Fuel delivery pipe having a damper function, characterized in that digit.   8. The fuel delivery pipe having a damper function according to claim 7, wherein the sound insulation cover is inserted into the mounting hole of the mounting bracket at a position corresponding to the mounting hole from the front wall portion to a part of the upper wall portion. Forming a notch for avoiding interference with the mounting bolt, and the front mounting piece extends from the lower edge of the front wall portion instead of the upper wall portion serving as the back of the notch. A fuel delivery pipe with a damper function characterized by extending from the leading edge.   9. The fuel delivery pipe having a damper function according to claim 1, wherein the fuel delivery pipe body includes a lower case made of the bottom plate portion and the ceiling formed integrally with each other. A damper comprising: a plate portion, front and rear plate portions, and an end plate portion; and an upper case that is liquid-tightly fixed on the upper side of the lower case and forms the internal space with the lower case. Fuel delivery pipe with functions.   The fuel delivery pipe having the damper function according to any one of claims 1 to 8, wherein the fuel delivery pipe body includes the bottom plate portion, the ceiling plate portion, and the front and rear portions formed integrally with each other. A fuel having a damper function, comprising: a cylindrical portion made of a plate portion; and a cap portion made of the end plate portion that is liquid-tightly fixed so as to close both ends of the cylindrical portion to form the internal space. Delivery pipe.

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