This application claims priority from Japanese Patent Application No. 2012-243358 filed on Nov. 5, 2012. The entire contents of the priority application are incorporated herein by reference.
The present disclosure relates to a delivery pipe, a pipe, and a method of producing a delivery pipe.
A known fuel delivery pipe (hereinafter, referred to as a delivery pipe) used in an internal-combustion engine is configured to distribute fuel delivered from a fuel supply pipe to a fuel injection valve provided for each cylinder. The delivery pipe includes a pipe having a distribution hole that extends in a thickness direction thereof. The fuel injection valve is connected to the distribution hole via a connection member such as a valve attachment. With this configuration, the fuel is supplied to the fuel injection valve from the delivery pipe. A mounting member is attached to an outer surface of the pipe of the delivery pipe to fix the delivery pipe to the internal-combustion engine.
A technology described herein relates to a delivery pipe that includes a pipe integrally including at least one cylindrical tube section and at least one flat tube section, and a valve attachment including a hollow cylindrical portion having a hollow cylindrical shape and a connection portion having a planar shape. The flat tube section includes a planar attachment portion having a distribution hole extending through the planar attachment portion in a thickness direction thereof. The hollow cylindrical portion has a closed end closed by the connection portion and is configured to be attached to a fuel injection valve. The connection portion has an introduction hole that extends through the connection portion in a thickness direction thereof and communicates with the distribution hole of the planar attachment portion. The valve attachment is connected to the planar attachment portion at a position adjacent to one of edges of the planar attachment portion. The edges of the planar attachment portion extend along an axial direction of the pipe.
The delivery pipes are configured to be used for various internal-combustion engines. For example, a delivery pipe has a configuration in which a valve attachment is attached to an outer surface of a pipe at a position away from an axis of the pipe in relation to an upper surface of a head portion of an engine to which the delivery pipe is attached. That is, the delivery pipe is arranged at an offset position.
When the fuel that is delivered through the delivery pipe is jetted from the fuel injection valve toward an engine, a reaction force may lead a large stress in a direction from the fuel injection valve to the pipe of the delivery pipe. In the delivery pipe to which the valve attachment is attached at the offset position, the large stress is applied to a connection portion at which the valve attachment is connected, if the pipe thereof is not fixed at a side corresponding to a side at which the valve attachment is attached to the pipe. Thus, the connection portion is pushed up to a side opposite to the fuel injection valve. The pipe may not withstand the stress. That is, the delivery pipe to which the valve attachment is attached at the offset position may have a lower strength.
Further, if a surface of the pipe that faces the engine is a curved surface and the curved surface is connected to the valve attachment at the offset position as in the known delivery pipe, the pipe and the valve attachment are required to be connected to each other at their curved surfaces facing each other. However, it is difficult to make the both curved surfaces to have the same curvature, and thus the curved surfaces are connected less tightly and a connection therebetween becomes complex compared to a case in which planar surfaces are connected to each other. Accordingly, the connection may be easily deformed by heat, and thus the strength of the pipe is less likely to be maintained.
The present technology has been made in view of the aforementioned circumstances. The technology disclosed herein provides a fuel delivery pipe in which the valve attachment is connected to the pipe at the offset position and the strength of the pipe is maintained.
(Configuration of Fuel Supply System for Automobile)
An embodiment will be described with reference to the drawings. As illustrated in
As illustrated in
The pressure adjuster 83 is configured to adjust the pressure of the fuel to be supplied to the fuel supply tube 85. The fuel transferred to the fuel supply tube 85 is sent to the delivery pipe 10 that is connected to the fuel supply tube 85. Then, the fuel in the delivery pipe 10 is delivered to fuel injection valves 60 (see
(Configuration of Delivery Pipe)
A right to left direction in
(Pipe)
The pipe 20 has an elongated tubular shape and is arranged in a horizontal position. The pipe 20 is arranged in a vehicle so as to extend in the right to left direction, i.e., in the vehicle width direction, for example. The pipe 20 has a main bore 20a extending through the pipe 20 along an axis thereof. The pipe 20 is made of stainless or iron, for example.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
(Valve Attachment)
As illustrated in
The connection portion 40a includes a circular introduction hole 40a1 that extends therethrough in the upper to lower direction, i.e., in a thickness direction thereof. The introduction hole 40a1 is positioned at substantially the center of a plate surface of the connection portion 40a. The introduction hole 40a1 is continuous from the attachment hole 40b1 of the cylindrical portion 40b. The valve attachment 40 is connected to the rectangular tube section 24 of the pipe 20 such that the connection portion 40a is in plane contact with the attachment portion 24a of the rectangular tube section 24. The connection portion 40a is arranged adjacent to the rear edge 24a2 of the attachment portion 24a that is positioned at the rear side and extends along the axial direction of the pipe 20. Further, the connection portion 40a is arranged such that the introduction hole 40a1 thereof overlaps with the distribution hole 24a1 that extends through the attachment portion 24a, and thus the introduction hole 40a1 communicates with the distribution hole 24a1 of the attachment portion 24a (see
(Mounting boss)
As illustrated in
The mounting bosses 50 each have a boss hole 50b extending therethrough along its axis. A fixture such as a bolt is inserted into the boss hole 50b. Then, the fixture is inserted and fixed to a fixation hole (not illustrated) provided in the head portion of the engine 73. Accordingly, the delivery pipe 10 is fixed to the head portion of the engine 73 via the mounting bosses 50.
According to the present embodiment, as illustrated in
(Connection Method of Valve Attachment)
A connection method of the valve attachment 40 and the pipe 20 will be described with reference to
Then, a welding or brazing is performed at a contact point between the attachment portion 24a and the connection portion 40a to connect them. As a result, the introduction hole 40a1 and the attachment hole 40b1 of the valve attachment 40 communicate with the main bore 20a and the distribution hole 24a1 of the pipe 20, and thus the fuel can be supplied from the pipe bore 20 to the fuel injection valve 60.
As described above, in the delivery pipe 10 according to the present embodiment, the connection portion 40a of the valve attachment 40 is connected to the attachment portion 24a of the flat tube section 24 at the position adjacent to one of the edges 24a3, 24a2 of the attachment portion 24a, i.e., the edge 24a2 on the rear side. That is, the valve attachment 40 is attached to the pipe 20 at the offset position. In the delivery pipe 10 according to the present embodiment, the pipe 20 and the valve attachment 40 are in plane contact at the attachment portion 24a and the connection portion 40a that have planar shape. Accordingly, even if the valve attachment 40 is attached to the pipe 20 at the offset position in accordance with the offset arrangement of the pipe 20 to the engine, the connection between the pipe 20 and the valve attachment 40 is not complex, and the pipe 20 and the valve attachment 40 is tightly connected. Thus, the strength of the pipe 20 can be maintained.
Further, in the delivery pipe 10 according to the present embodiment, the mounting bosses 50 are each attached to the outer surface of the circular tube section 22 to fix the pipe 20 (the circular tube section 22). The mounting bosses 50 are each attached at the side 22a of the circular tube section 22 that corresponds to the side at which the valve attachment 40 is connected to the rectangular tube section 24. Accordingly, even if a large stress is applied in a connection between the pipe 20 and the valve attachment 40 in a direction from the fuel injection valve 60 to the pipe 20, the pipe 20 is hardly pushed up at the connection in a direction opposite to the fuel injection valve 60 (in an upper direction). Even if the fuel that is delivered through the delivery pipe 10 is jetted from the fuel injection valve 60 toward the engine 73, the strength of the pipe 20 is maintained. In the above-described delivery pipe 10, the strength of the pipe 20 is maintained while the valve attachment 40 is attached to the pipe 20 at the offset position.
In the delivery pipe 10 according to the present embodiment, the rectangular tube section 24 has the dimension larger than the diameter of the circular tube section 22 such that the rectangular tube section 24 has the protruding portion that is positioned outward of the outer surface of the circular tube section 22. The dimension is measured in the direction perpendicular to the axial direction of the pipe 20 along the attachment portion 24a. The protruding portion overlaps with at least a part of the mounting boss 50 in the axial direction of the pipe 20 (the right to left direction). With this configuration, a space next to the outer surface of the circular tube section 22 that overlaps with the protruding portion of the rectangular tube section 24 in the axial direction of the pipe 20 can be used as a space for the mounting boss 50. This makes an effective use of the space next to the pipe 20 and saves the space required in the arrangement of the pipe 20 to the engine.
In the delivery pipe 10 according to the present embodiment, the parts of the hollow cylindrical tube are pressed to obtain the rectangular tube sections 24. Accordingly, the pipe 20 integrally includes the rectangular tube sections 24 and the circular tube sections 22 without seam. Further, the pipe 20 integrally including the circular tube sections 22 and the flat tube sections 24 that are coaxially arranged can be easily produced. Due to the pressing process in the production process of the delivery pipe 10, the pipe 20 that integrally includes the circular tube sections 22 and the rectangular tube sections 24 coaxially arranged with smooth connection can be easily produced. In addition, the hollow cylindrical tube is pressed to obtain the rectangular tube sections 24 and the circular tube sections 22 that are alternately arranged. Accordingly, the rectangular tube sections 24 each have the protruding portion that is positioned outward of the outer surface of the circular tube section 22. Thus, a space where the mounting boss 50 is arranged can be provided between the adjacent rectangular tube sections 24. The mounting bosses 50 can be arranged between adjacent rectangular tube sections 24 each of which is connected to the valve attachment 40. With this configuration, the pipe 20 can be properly fixed by the mounting bosses 50.
In the above described delivery pipe, the connection portion of the valve attachment is connected to the planar attachment portion of the flat tube section at the position adjacent to one of the edges of the attachment portion. That is, the valve attachment is attached to the pipe at the offset position. In the above-described delivery pipe, the pipe and the valve attachment are connected at the attachment portion and the connection portion that are planar in shape. Accordingly, even if the valve attachment is attached to the pipe that includes the valve attachment at the offset position, the connection between the pipe and the valve attachment is not complex and the pipe and the valve attachment is tightly connected, and thus the strength of the pipe can be maintained.
The above-described delivery pipe may further include a mounting member attached to an outer surface of the cylindrical tube section at a side corresponding to the one of the edges of the planar attachment portion. The mounting member is configured to maintain the cylindrical tube section in a fixed position.
In the above described delivery pipe, the mounting member is attached to the outer surface of the cylindrical tube section to fix the pipe. The mounting member is attached at the side that corresponds to the one of the edges of the planar attachment portion. With this configuration, even if a large stress is applied to a connection between the pipe and the valve attachment in a direction from the fuel injection valve to the pipe, the pipe is hardly pushed up at the connection in a direction opposite to the fuel injection valve. Accordingly, even if the fuel that is delivered through the delivery pipe is jetted from the fuel injection valve toward an engine, the strength of the pipe is maintained. In the above-described delivery pipe, the strength of the pipe is maintained while the valve attachment is attached to the pipe at the offset position.
In the above-described delivery pipe, the flat tube section may have a dimension in a direction perpendicular to the axial direction of the pipe along the attachment portion that is larger than a diameter of the cylindrical tube section such that the flat tube section has a protruding portion positioned outward of the outer surface of the cylindrical tube section. The protruding portion may overlap with at least a part of the mounting member in the axial direction of the pipe.
With this configuration, a space next to the outer surface of the cylindrical tube section that overlaps with the protruding portion of the flat tube section in the axial direction of the pipe can be used as a space for the mounting member. This makes an effective use of the space next to the pipe and saves the space required in the arrangement of the pipe to the engine.
In the above-described delivery pipe, the at least one cylindrical tube section may include a plurality of cylindrical tube sections and the at least one flat tube section may include a plurality of flat tube sections. The pipe may alternately include each of the cylindrical tube sections and each of the flat tube sections. The cylindrical tube sections and the flat tube sections may be coaxially arranged.
The valve attachment may be connected to the planar attachment portion at a position closer to the edge of the planar attachment portion than half of a dimension of the planer attachment portion in a direction perpendicular to the axial direction of the pipe.
The cylindrical tube section may have a circular cross-section taken along a line perpendicular to an axis thereof, and the flat tube section may have a rectangular cross-section taken along a line perpendicular to an axis thereof.
The delivery pipe may have a straight axis.
The introduction hole of the connection portion of the valve attachment may be positioned at substantially a center of the connection portion. The distribution hole of the planar attachment portion of the flat tube section may be positioned adjacent to the one of the edges of the planar attachment portion. The introduction hole and the distribution hole are coaxially arranged.
The distribution hole may have a diameter substantially equal to a diameter of the introduction hole.
The technology disclosed herein may be embodied as a pipe that includes a cylindrical tube section and a flat tube section including a planar attachment portion having a distribution hole. The distribution hole extends through the planar attachment portion in a thickness direction thereof. The flat tube section may have a dimension in a direction perpendicular to an axial direction of the flat tube section along the planar attachment portion that is larger than a diameter of the round tube section such that the flat tube section has a protruding portion that is positioned outward of the outer surface of the round tube section. At least a part of the distribution hole may be positioned in the protruding portion of the flat tube section.
The technology disclosed herein may be embodied as a method of producing a delivery pipe that includes providing a cylindrical hollow tube, pressing a part of the cylindrical hollow tube to have a flat tube section having a planar attachment portion, forming a distribution hole extending through the planar attachment portion in a thickness direction thereof, providing a valve attachment including a hollow cylindrical portion and a connection portion having a planar shape, attaching the valve attachment to the planar attachment portion at a position adjacent to one of edges of the planar attachment portion such that the introduction hole thereof communicates with the distribution hole of the planar attachment portion. A remaining part of the cylindrical hollow tube may be a cylindrical tube section. The hollow cylindrical portion may have a closed end closed by the flat connection portion. The connection portion may have an introduction hole extending through the connection portion in a thickness direction thereof.
The method may further include attaching amounting member to an outer surface of the cylindrical tube section at a side corresponding to the one of the edges of the planar attachment portion.
The above-described pipe is obtained by pressing apart of the cylindrical hollow tube, for example. Accordingly, the pipe integrally includes the cylindrical tube section and the flat tube section without seam. Further, the pipe integrally including the cylindrical tube section and the flat tube section that are coaxially arranged can be easily produced. In addition, since the cylindrical hollow tube is pressed to obtain the flat tube section that is positioned between the cylindrical tube sections, the flat tube section has a protruding portion that is positioned outward of the outer surface of the cylindrical tube section. Accordingly, a space where the mounting boss is arranged can be provided between the adjacent flat tube sections. Thus, the mounting member can be arranged between adjacent flat tube sections each of which is connected to the valve attachment. With this configuration, the pipe can be properly fixed by the mounting member.
The technology described herein provides the delivery pipe in which the valve attachment is connected to the pipe at the offset position and the strength of the delivery pipe is maintained.
The present invention is not limited to the embodiments as described above with reference to the drawings. For example, the present invention may include following embodiments.
(1) According to the above-described present embodiment, the distribution hole 24a1 in the pipe 20 is positioned adjacent to the rear edge 24a2 of the attachment portion 24a. However, the distribution hole 24a1 and the introduction hole 40a1 may be positioned at any position and may have any shape as long as the distribution hole 24a1 and the introduction hole 40a1 communicate with each other and the connection portion 40a is connected to the attachment portion 24a at a position adjacent to one of edges of the attachment portion 24a.
(2) According to the above embodiment, the connection portion 40a of the valve attachment 40 is connected to the attachment portion 24a of the rectangular tube section 24 included in the pipe 20 at the position adjacent to the rear edge 24a2 of the attachment portion 24a. However, the connection portion 40a of the valve attachment 40 may be connected to the attachment portion 24a at a position adjacent to the front edge 24a3. In such a case, the mounting boss 50 may be attached to the circular tube section 22 of the pipe 20 at a front side thereof.
(3) According to the above embodiment, the pipe 20 is arranged in a vehicle so as to extend in the right to left direction, i.e., in the width direction of the vehicle. However, the pipe 20 may be arranged in a vehicle so as to extend in the front to rear direction, i.e., in a longitudinal direction of the vehicle. In such a case, the connection portion 40a of the valve attachment 40 may be connected to the attachment portion 24a of the rectangular tube section 24 of the pipe 20 at a position adjacent to either one of right and left edges of the attachment portion 24a. The mounting boss 50 may be attached to the circular tube section 22 at either one of right and left sides.
(4) According to the above embodiment, adjacent circular tube sections 22 are equally spaced apart from each other and adjacent rectangular tube sections 24 are equally spaced apart from each other. However, the adjacent circular tube sections 22 may not be equally spaced apart from each other and the rectangular tube sections 24 may not be equally spaced apart from each other.
(5) The connection portion 40a and the pipe 20 may be connected in a different manner from the above embodiment and the mounting boss 50 and the pipe 20 may be connected in a different manner from the above embodiment.
(6) In the above embodiment, the pipe 20 includes the rectangular tube section 24 that has a rectangular cross-section taken along a line perpendicular to the axis of the pipe 20. However, the rectangular tube section 24 may have any shape in cross section as long as the planar attachment portion 24a is included. The cross section may be substantially oval shape or any quadrangular shape.
The embodiment is explained in detail above for illustrative propose only, and it is to be understood that the claims are not limited by the forgoing description. The technology described in the claims includes the various modifications of the embodiments described above.
The technology components described in the description and the drawings are not required to be used in the combination described in the claims as originally filed. The technology components can show its technical utility when used either alone or in combination. In addition, the technology described in the above description and the drawings can achieve more than one object at the same time, and the technical utility of the technology can be recognized when the technology achieves one of the objects.
Number | Date | Country | Kind |
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2012-243358 | Nov 2012 | JP | national |