JP2013199884A - Fuel distribution pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an orifice diameter without degrading quality of plating.SOLUTION: A fuel distribution pipe includes: a delivery pipe 20 that has a flow passage having a second flow passage 23A branched from a first flow passage 21A and being subjected to plating process on the wall thereof; a fuel pipe 40 that has a third flow passage 40A connected to the end part opposite to the connection part of the first flow passage 21A in the second flow passage 23A; a metal member 60 that has an orifice 61 that makes the second flow passage 23A communicate with the third flow passage 40A; and a nut 50 that fixes the fuel pipe 40 to the delivery pipe 20 by sandwiching the metal member 60 between an opening 24 of the second flow passage 23A and an opening 41 of the third flow passage 40A.

Description

  The present invention relates to a fuel distribution pipe.

  Conventionally, as a fuel distribution pipe provided with an orifice in a fuel flow path in order to reduce fuel pulsation, for example, one described in Patent Document 1 below is known. In this device, a branching cylinder part is provided on the outer periphery of the main pipe, and a first flow path is provided inside the main pipe, while a second flow path is provided inside the branching cylinder part. The fuel is branched to the second flow path through the first flow path. An orifice is formed at a connection portion of the second flow path with the first flow path. The orifice is provided to reduce fuel pulsation.

JP 2011-226353 A

  However, the above-mentioned orifice is obtained by inserting a small diameter drill from the tip of the branching cylinder part through the second flow path to a deep position and cutting the boundary portion between the first flow path and the second flow path. Since it is formed, the machinability is poor. For this reason, a burr | flash etc. generate | occur | produce on the wall surface which comprises an orifice, and the quality of plating worsens. On the other hand, the higher the fuel pressure, the greater the fuel pulsation. To reduce the fuel pulsation, it is necessary to further reduce the diameter of the orifice. There is concern about further deterioration of machinability. Further, when the diameter of the orifice is reduced, it is difficult for the plating solution to circulate around the periphery of the orifice wall surface, so that the plating quality is reduced due to a decrease in the thickness of the plating.

  The present invention has been completed based on the above situation, and an object thereof is to reduce the diameter of an orifice without deteriorating the quality of plating.

  The present invention has a flow path in which a second flow path is branched from a first flow path, and a delivery pipe whose wall surface constituting the flow path is plated, and a first flow in the second flow path. A fuel pipe having a third flow path connected to an end opposite to the connection portion with the path, a metal material in which an orifice for communicating the second flow path and the third flow path is formed, and the second flow path And a joint member for fixing the fuel pipe to the delivery pipe by sandwiching a metal material between the opening and the opening of the third flow path.

  According to such a configuration, the metal material in which the orifice is formed is configured separately from the delivery pipe, so that it is not necessary to insert a small-diameter drill or the like deeply, and the cutting performance of the orifice is improved. Can do. Therefore, burrs and the like are less likely to occur on the wall surface constituting the orifice. Further, even if burrs or the like occur, it can be expected that work such as deburring can be facilitated and visual inspection can be facilitated by making the metal material separate from the delivery pipe. Therefore, it becomes easy to perform the plating process on the wall surface constituting the orifice, and the quality of plating at the orifice can be improved.

  Further, according to the above configuration, since the orifice is not formed in the delivery pipe but the orifice is formed in the metal material, the narrow portion is not formed in the flow path of the delivery pipe. As a result, there is no possibility of inhibiting the circulation of the plating solution flowing in the flow path of the delivery pipe, and it becomes easy to perform the plating process on the wall surface constituting the flow path, and the quality of the plating in the delivery pipe can be improved.

The following configuration is preferable as an embodiment of the present invention.
The metal material may be made of stainless steel.
According to such a configuration, for example, when alcohol fuel is used, there is no possibility that the metal material corrodes, and the wall surface of the orifice does not need to be plated.

The opening part of the second channel may have a receiving surface having a mortar shape, and the opening part of the third channel may have a pressing surface having a mortar shape.
According to such a configuration, the metal material can be placed on the receiving surface, and the metal material can be pressed by the pressing surface.

A joint member is good also as a structure which pushes in the opening part of a 3rd flow path in the direction which a press surface presses the metal material mounted in the receiving surface.
According to such a configuration, the metal member can be pushed toward the pressing surface by attaching the joint member to the delivery pipe.

The joint member is configured to include a cylindrical body that covers a range from the opening of the second flow path to the opening of the third flow path, and a back wall in which an insertion hole through which the fuel pipe is inserted is formed. It is good.
According to such a configuration, the metal material can be covered with the cylindrical body and the back wall while the fuel pipe is inserted through the insertion hole.

  According to the present invention, the diameter of the orifice can be reduced without reducing the quality of plating.

Sectional view showing the overall structure of the fuel distribution pipe Sectional view showing the state before the fuel pipe is fixed to the delivery pipe Sectional drawing which shows the state after fixing a fuel piping to a delivery pipe by pinching | interposing a metal material between the opening part of a 2nd flow path, and the opening part of a 3rd flow path with a coupling member

<Embodiment>
An embodiment of the present invention will be described with reference to the drawings of FIGS. As shown in FIG. 1, the fuel distribution pipe 10 in this embodiment includes a delivery pipe 20 that distributes fuel such as gasoline sent from a fuel tank to a plurality of injectors 30, and a fuel that supplies fuel to the delivery pipe 20. A pipe 40 and a nut 50 for fixing the fuel pipe 40 to the delivery pipe 20 are provided.

  The delivery pipe 20 includes a main pipe 21 extending in the horizontal direction, a branching cylinder part 22 connected to a plurality of injectors 30, and a fuel pipe cylinder part 23 connected to a fuel pipe 40. A first flow path 21 A is formed inside the main pipe 21, a branch flow path 22 A is formed inside the branching cylinder part 22, and a second flow path 23 A is formed inside the fuel pipe cylinder part 23. Is formed. The first channel 21A, the second channel 23A, and the branch channel 22A communicate with each other. Nickel phosphorous plating treatment is applied to the wall surface constituting the flow path composed of the first flow path 21A and the second flow path 23A.

  The branching cylinder part 22 is configured to protrude from the outer periphery of the main pipe 21 in a direction orthogonal to the axial direction of the main pipe 21, and each of the branching cylinder parts 22 is configured to protrude in the same direction in the axial direction of the main pipe 21. Are arranged side by side. On the other hand, the fuel pipe cylinder portion 23 is configured to protrude from the outer periphery of the main pipe 21 in a direction orthogonal to the axial direction of the main pipe 21, and protrudes in a direction opposite to the protruding direction of the branching cylinder portion 22 around the axis line of the main pipe 21. ing.

  As shown in FIG. 2, the fuel pipe cylinder 23 has an opening 24 formed at the upper end of the second flow path 23A. A mortar-shaped receiving surface 25 is formed on the peripheral edge of the second flow path 23 </ b> A in the opening 24. A male screw is screwed on the outer peripheral surface of the fuel pipe cylinder portion 23.

  The fuel pipe 40 can be connected to the opening 24 of the fuel pipe cylinder portion 23. A third flow path 40 </ b> A is formed inside the fuel pipe 40. The fuel pipe 40 has an opening 41 formed at the lower end of the third flow path 40A. A pressing surface 42 having a mortar shape is formed on the peripheral edge of the third flow path 40 </ b> A in the opening 41. An engaging surface 43 that is parallel to the pressing surface 42 is formed at a portion corresponding to the opening 41 on the outer periphery of the fuel pipe 40.

  The nut 50 has a substantially bag shape, and includes a cylindrical cylinder 51 and a back wall 52 formed at the upper end of the cylinder 51. On the inner periphery of the cylinder 51, a female screw is screwed. When the nut 50 is externally fitted to the fuel pipe cylinder portion 23 and rotated, the nut 50 is fastened to the fuel pipe cylinder portion 23 by screwing the female screw of the cylinder body 51 with the male screw of the fuel pipe cylinder portion 23. . An insertion hole 53 through which the fuel pipe 40 is inserted is formed in the back wall 52. A sliding surface 54 having a mortar shape is formed at the lower end portion of the insertion hole 53 in the fuel pipe 40. The sliding surface 54 engages with the engaging surface 43 of the fuel pipe 40 while sliding with the nut 50.

  When the nut 50 is tightened into the fuel pipe cylinder 23, the metal material 60 is sandwiched between the receiving surface 25 of the fuel pipe cylinder 23 and the pressing surface 42 of the fuel pipe 40, and the fuel pipe 40 is connected to the fuel pipe cylinder. It is fixed to the part 23. In this state, the third flow path 40A of the fuel pipe 40 and the second flow path 23A of the fuel pipe cylinder 23 are connected in a sealed state by the metal material 60, and the flow paths 40A and 23A are mutually connected via the orifice 61. Communicate.

  Now, a metal material 60 made of stainless steel is sandwiched between the opening 24 of the fuel pipe cylinder 23 and the opening 41 of the fuel pipe 40 in the present embodiment. At the axial center position of the metal material 60, an orifice 61 is formed penetrating in the vertical direction. The orifice 61 is provided to reduce fuel pulsation, and has a smaller diameter than the third flow path 40A of the fuel pipe 40 and a smaller diameter than the second flow path 23A of the fuel pipe cylinder portion 23. It is said that. The metal material 60 has a block shape with a substantially circular cross section. An upper tapered surface 62 that can come into contact with the pressing surface 42 of the fuel pipe 40 is formed on the outer peripheral edge portion of the upper surface of the metal material 60, and the fuel pipe cylinder portion 23 is formed on the outer peripheral edge portion of the lower surface of the metal material 60. A lower taper surface 63 that can contact the receiving surface 25 is formed.

  Such a metal material 60 is formed by cutting. In particular, the orifice 61 is processed by a small diameter drill. In drilling, since the length from the base of the drill to the tip can be shortened, the machinability can be improved. Therefore, the occurrence of burrs or the like on the inner wall of the orifice 61 can be restricted. Even if burrs or the like are generated, the metal material 60 can be easily visually inspected, and operations such as deburring can be easily performed.

  In this embodiment, although the surface of the metal material 60 is not plated, the quality of the plating applied to the inner wall of the orifice 61 even if the metal material 60 is plated. Can be improved. The plating quality here means, for example, that the film thickness of the plating is stable, that there is no discoloration or pinhole on the surface of the plating, or that there is no peeling of the plating.

  On the other hand, the delivery pipe 20 is formed by hot forging. The plating process is performed on the delivery pipe 20 by circulating the plating solution through the first flow path 21A and the second flow path 23A. At this time, since there is no narrow portion like the orifice 61 in the delivery pipe 20, the circulation of the plating solution is hindered and the quality of the plating does not deteriorate. Therefore, high-quality plating can be performed on both the wall surface constituting the first flow path 21A and the wall surface constituting the second flow path 23A.

  Further, in order to restrict the increase in fuel pulsation as the fuel pressure increases, it is desired to further reduce the diameter of the orifice. However, there is a limit to forming such a small diameter orifice by hot forging. . In that regard, by configuring the orifice material separately from the delivery pipe as in this embodiment, it becomes possible to form the orifice by cutting that can cope with a smaller diameter than hot forging. It is possible to reduce the diameter.

  Further, since the metal material 60 is not press-fitted into the delivery pipe 20 but is connected by pressing the lower taper surface 63 to the receiving surface 25, the second flow path 23A of the delivery pipe 20 is configured. There is no fear that the nickel phosphorus plating film formed on the wall surface is scraped off.

  In addition, since the range from the opening 24 of the fuel pipe cylinder 23 to the opening 41 of the fuel pipe 40 can be covered with the bag-like nut 50, the nut 50 can be protected.

  When the fuel pipe 40 and the fuel pipe cylinder portion 23 are connected, the lower taper surface 63 of the metal material 60 is placed on the receiving surface 25 and the nut 50 is tightened into the fuel pipe cylinder portion 23. Since the upper tapered surface 62 can be pressed from above by the pressing surface 42, the connection work can be easily performed.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) Although the metal material 60 is not subjected to nickel phosphorous plating in the above embodiment, the present invention includes those in which the metal material is subjected to nickel phosphorous plating. Further, the type of plating treatment is not limited to nickel phosphorus plating treatment.

  (2) Although the fuel pipe 40 is fixed to the fuel pipe cylinder 23 by screwing the nut 50 into the fuel pipe cylinder 23 in the above embodiment, the nut is bolted to the main pipe 21 according to the present invention. For example, the fuel pipe 40 may be fixed to the fuel pipe cylinder portion 23.

  (3) Both the thing which applied the nickel phosphorus plating process to the wall surface which comprises the 3rd flow path 40A of the fuel piping 40, and the thing which does not give are included in this invention.

  (4) In the above embodiment, the fuel distribution pipe is applied to the fuel distribution pipe 10 used for a gasoline engine. However, according to the present invention, the fuel distribution pipe may be applied to a common rail used for a diesel engine.

10 ... Fuel distribution pipe 20 ... Delivery pipe 21A ... First flow path 23A ... Second flow path 24 ... Opening 25 ... Receiving surface 40 ... Fuel pipe 40A ... .Third flow path 41 ... Opening 42 ... Pressing surface 50 ... Nut (joint member)
51 ... Cylinder 52 ... Back wall 53 ... Insertion hole 60 ... Metal material 61 ... Orifice

Claims (5)

A delivery pipe having a flow path formed by branching the second flow path from the first flow path, and a plating treatment applied to the wall surface constituting the flow path;
A fuel pipe having a third flow path connected to an end of the second flow path opposite to the connection with the first flow path;
A metal material in which an orifice for communicating the second flow path and the third flow path is formed;
A fuel distribution pipe comprising: a joint member that sandwiches the metal material between the opening of the second flow path and the opening of the third flow path and fixes the fuel pipe to the delivery pipe.   The fuel distribution pipe according to claim 1, wherein the metal material is made of stainless steel.   The opening of the second flow path has a receiving surface having a mortar shape, and the opening of the third flow path has a pressing surface having a mortar shape. 2. Fuel distribution pipe according to 2.   4. The fuel distribution pipe according to claim 3, wherein the joint member pushes the opening of the third flow path in a direction in which the pressing surface presses the metal material placed on the receiving surface. 5.   The joint member includes a cylindrical body that covers a range from the opening of the second flow path to the opening of the third flow path, and a back wall in which an insertion hole through which the fuel pipe is inserted is formed. The fuel distribution pipe according to any one of claims 1 to 4, wherein the fuel distribution pipe is provided.

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