JP2004082182A - Tubular body for rocker shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a tubular body for rocker shafts of an internal combustion engine which has a plurality of flow passages without the fear of the leakage of the circulating fluid between respective flow passages in the interior at a low cost and by lightening the weight in a relatively simple manufacturing process. <P>SOLUTION: This cylindrical tubular body (10) has a plurality of internal spaces (11a, 11b) each of which is divided from the other and which are extended along the axial line. A plurality of single tubular bodies having a single internal space respectively are formed as a circular arc part A by which a cylindrical outer peripheral surface is formed by forming a joined part T where part of an outer peripheral surface of these single tubular bodies is brought into surface contact with part of the outer peripheral surface of the other single tubular body, combining the other part of the outer peripheral surface of the single tubular body to the outer peripheral surface of the other single tubular body and welding or brazing mutual joined parts where a plurality of single tubular bodies are brought into surface contact. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiway pipe, and more particularly to a pipe for a rocker shaft of an internal combustion engine. More specifically, the present invention relates to a rocker shaft tube for an internal combustion engine that is inexpensive to manufacture and lightweight.
[0002]
[Prior art]
In addition to those that function as structural materials, pipes that are incorporated into some of various machines such as internal combustion engines, industrial machines, etc. Some have both a function and a function as a flow path forming body.
[0003]
Generally, a pipe as a flow path forming body is one in which one flow path is formed inside. In such a case, for example, a spiral welded pipe, a UOE welded pipe, a press & roll Conventional pipes such as bending welded pipes, hot-finished or cold-finished seamless pipes, ERW pipes, forged pipes, hot-finished ERW pipes, hot-extrusion seamless pipes, etc. may be used. However, for example, there are cases where a plurality of flow paths are arranged inside one pipe body because it is necessary to arrange them in a limited space. For example, in a rocker shaft for an internal combustion engine, it is necessary to separately flow lubricating oil and hydraulic oil for opening and closing a valve without mixing them.
[0004]
In this case, conventionally, for example, a plurality of hole portions are formed on a solid round bar along its axis by using a machine tool such as a cutting drill. With a machine, there is a limit to the depth at which drilling is possible, workability is poor, and it is not easy to accurately form a hole passage parallel to the axis.
[0005]
Japanese Unexamined Patent Publication No. 4-134104 discloses a rocker shaft as an example of a multi-way pipe body, in which an inner cylinder having a recess having a predetermined axial length is press-fitted into an outer cylinder, and the inner cylinder and the recess are formed. And a plurality of flow paths are proposed.
[0006]
Further, in Japanese Patent Application Laid-Open No. 8-150412, an outer tube is formed of an outer tube and an inner tube, and an outer peripheral surface of the inner wall of the inner wall of the inner wall of the inner tube that extends over half of the entire circumference is continuous with the inner peripheral surface of the outer tube. The inner tube has a first portion inside the inner tube between the outer peripheral surface of the concave portion and the inner peripheral surface of the outer tube by forming a concave portion having a concave shape so as to protrude toward the inside of the tube. A pipe having an internal partition wall, characterized in that a second space isolated from the above-mentioned space is formed.
[0007]
As described in JP-A-4-134104 and JP-A-8-150412, when a plurality of pipes are combined to form a multi-way pipe, the two pipes are joined to an outer cylinder by an inner cylinder. This is performed by pressing the cylinders. For this reason, depending on the strength relationship between the pipes, there is a high possibility that the roundness of the cross section of the outer pipe may be impaired, or that the cross section of the inner pipe may have an irregular shape such as a wavy shape or a wrinkled shape. Also, from the viewpoint of workability, the operation of press-fitting the inner cylinder involves difficulties.Furthermore, it is necessary to make the wall thickness of the tube more than a predetermined value so as to withstand the operation of pressure welding. It led to weight increase. In addition, since the flow path is formed by pressing the inner cylinder against the outer cylinder, there is a possibility that a gap may be formed in the pressure contact surface. For example, in the case where a communication hole is provided along the radial direction of the tube from the outside of the tube with respect to the flow path formed by the inner cylinder of the tube, and the fluid is taken out of the tube, the above-described case is described. There is a possibility that the fluid flowing on the outer cylinder side leaks from such a gap in the pressure contact surface and mixes with the inside of the fluid flowing on the inner cylinder side.
[0008]
[Problems to be solved by the invention]
Accordingly, it is an object of the present invention to provide a novel rocker shaft tube for an internal combustion engine which solves the above-mentioned problems in the prior art. In particular, an object of the present invention is to provide a tube for a rocker shaft of an internal combustion engine that can be manufactured at a low cost by a relatively simple manufacturing process and that can be reduced in weight.
[0009]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is a cylindrical pipe having a plurality of internal spaces which are partitioned from each other and extended along an axis, and a plurality of single pipes each having a single internal space, A part of the outer peripheral surface of these single tubes forms a joint portion that comes into surface contact with a part of the outer peripheral surface of another single tube, and the remaining portion of the outer peripheral surface of the single tube forms another unit. It is formed by combining with the rest of the outer peripheral surface of the tubular body to form a cylindrical outer peripheral surface, and is formed by welding or brazing the joint portions of the plurality of single tubular bodies that are in surface contact with each other. 1 shows a tube for a rocker shaft of an internal combustion engine, characterized by the following.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0011]
FIG. 1 is a partially sectional perspective view showing a structure of an embodiment of a multi-way tube for a rocker shaft according to the present invention. FIG. 2 is a cross-sectional view showing the structure of another embodiment of a multi-way pipe for a rocker shaft according to the present invention, and FIG. 3 is a cross-sectional view showing one state in a manufacturing process of the multi-way pipe according to the present invention. FIG.
[0012]
As shown in the embodiment shown in FIGS. 1 and 2, a multi-way pipe for a rocker shaft (hereinafter, simply referred to as “multi-way pipe”) 10 of the present invention is partitioned from each other, and It has a plurality of internal spaces 11a, 11b, 11c... Extending along the axis of the body. The internal spaces 11a, 11b, 11c,... Are not particularly limited. However, at any position in the axial direction of the multi-way pipe, the cross-sectional shape in the radial cross-section is substantially the same. Preferably, it is formed.
[0013]
.. Having a plurality of internal spaces 11a, 11b, 11c... Are manufactured by combining and joining a plurality of single tubes 12a, 12b, 12c. Things. That is, in obtaining the multi-way pipe body 10 according to the present invention, first, as shown in FIG. 3, a plurality of single pipe bodies 12a, 12b, and 12c each having a single internal space are formed by combining these single pipe bodies. A part of the outer peripheral surface forms a joint portion T that is in surface contact with a part of the outer peripheral surface of another single tube body, and the remaining part of the outer peripheral surface of the tube body is the remaining part of the outer peripheral surface of the other single tube body. In combination with the above, molding is performed so as to have an arc portion A that forms a cylindrical outer peripheral surface. The joining portions T that come into face-to-face contact with each other are not limited to those having a substantially planar shape as shown in FIGS. 3A and 3C, as long as they can be brought into close contact by welding or brazing as described later. As shown in FIG. 3 (b), the concave and convex curved surfaces may correspond to each other, or may be other. On the other hand, the arc portion A may be such that the sum of the respective arc portions of the plurality of combined single tubes forms a substantially circular body, and the lengths of the arc portions A of the respective tubes are different from each other. May be substantially the same or different. Then, the plurality of single pipe bodies are combined and formed by welding or brazing the joint portions T that are in surface contact with each other.
[0014]
In the multi-way pipe of the present invention, the number of the plurality of internal spaces extending along the axis of the multi-way pipe is not particularly limited. It is possible to use two as shown in FIG. 2A, or three or more as shown in FIG. 2B.
[0015]
The cross-sectional area ratios of the internal spaces 11a, 11b, 11c... Are not particularly limited, and may be substantially equal in size, or one may have a smaller diameter than the other, depending on the application. It is possible.
[0016]
The cross-sectional shape of each of the internal spaces 11a, 11b, 11c... Is not particularly limited, but, for example, a sharp edge or the like causes abnormal fluid flow, retention of the fluid, etc., resulting in corrosion damage. Since there is a possibility that formation is generally avoided as much as possible, it is preferable that the shape does not include such a portion.
[0017]
The single pipe used for manufacturing the multi-way pipe of the present invention is not particularly limited as long as it can be formed into the desired shape as described above, and can be welded or brazed. Depending on the application of the multi-way pipe, for example, various steel pipes, copper or copper alloy pipes such as copper and brass, various metal or metal alloy pipes such as aluminum or aluminum alloy pipes can be exemplified. The production method is not particularly limited. Spiral welded pipe, UOE welded pipe, press & roll bending welded pipe, hot-finished or cold-finished seamless pipe, ERW pipe, forged pipe, hot-finished ERW Various materials such as a tube and a hot extrusion seamless tube can be used.
[0018]
It should be noted that the single tube having the desired shape as described above can be naturally obtained by directly manufacturing a tube having a modified cross section, but usually, a general round tube is subjected to cold drawing or pressing. It is preferable in terms of cost to obtain by deforming by secondary processing by a known method.
[0019]
Also, the method of welding or brazing can be appropriately selected from various known methods depending on the type of the plate material to be used and the use of the multi-way pipe.
[0020]
The multi-way pipe of the present invention has a cylindrical shape with a circular cross-sectional outer shape. However, in order to obtain a desired diameter and improve the roundness of the cross-section, for example, a plurality of single pipes as described above are used. After the welding or brazing step, a step such as cold drawing can be performed as necessary.
[0021]
The multi-way pipe of the present invention obtained in this manner has a plurality of flow paths partitioned inside, and is light in weight and inexpensive. Suitable for various applications such as various pipes that simultaneously allow a plurality of different fluids to flow through the pipe, such as a rocker shaft for an internal combustion engine, a pipe for lubricating oil and fuel oil, or a pipe for a heat exchanger. You can do it.
[0022]
FIG. 4 is a partial cross-sectional front view showing the structure of an example of a rocker shaft using the multiway pipe of the present invention.
[0023]
The rocker shaft 20 shown in FIG. 4 is manufactured by processing a multi-way pipe body 10 having a cross-sectional shape as shown in FIG. 1, and both open ends of the pipe are closed by mounting plugs 21a and 21b. Have been. In each of the plugs 21a and 21b, a through hole 23 which is an oil introduction port to the first internal space 11a of the tube 10 is formed. The upper side wall of the tube 10 in FIG. A through hole 24 is formed as an oil outlet from the space 11a. In addition, a through hole 25 as an oil inlet and an through hole 26 as an oil outlet to the second internal space 11b are formed in the lower side wall of the tube 10 in FIG.
[0024]
In FIG. 4, reference numeral 27 denotes a notch formed in the tubular body 10. The notch 27 serves to prevent the rocker shaft 20 from interfering with a bolt for attaching the rocker shaft 20 to a fixing member such as a cylinder head (not shown) by a rocker shaft holder (not shown). To avoid. Oil leaking from the clearance between the notch 27 and the bolt is used as lubricating oil for the rocker shaft holder.
[0025]
As described above, the multipath pipe body of the present invention can be configured such that the first internal space 11a and the second internal space 11b of the pipe body are separated from each other only by attaching the ends 21a and 21b for closing the ends. In the case of the rocker shaft, fluids having different purposes, for example, lubricating oil for cooling the engine and hydraulic oil for operating the engine brake mechanism can simultaneously flow in the respective spaces 11a and 11b without inconvenience. it can.
[0026]
【The invention's effect】
As described above, the rocker shaft multiway pipe of the present invention includes a plurality of single pipes each having a single internal space, and a part of the outer peripheral surface of each of these single pipes is formed of another single pipe. Forming a joint portion that is in surface contact with a part of the outer peripheral surface, and the remaining portion of the outer peripheral surface of the single tube is combined with the remaining portion of the outer peripheral surface of the other single tube to form a cylindrical outer peripheral surface. Since it is formed by forming and forming by welding or brazing the joint portions of the plurality of single pipes which are in surface contact with each other, the plurality of internal spaces are surely partitioned without leakage of fluid. The pipe body can be manufactured at a low cost by a relatively simple manufacturing process, and the weight can be reduced.
[0027]
Further, if the rocker shaft is manufactured by using the multi-way pipe for a rocker shaft of the present invention, there is no risk of mixing of a plurality of fluids flowing inside, and reliability can be ensured even as a flow path of a plurality of fluids. Further, since it can be formed by processing a plate material, it can be configured as a relatively lightweight one, which can also contribute to reducing the weight of the engine head.
[Brief description of the drawings]
FIG. 1 is a partially sectional perspective view showing a structure of an embodiment of a multi-way pipe according to the present invention.
FIGS. 2A and 2B are cross-sectional views each showing a structure of another embodiment of a multi-way pipe according to the present invention.
FIGS. 3A to 3C are cross-sectional views each showing a state of a process of manufacturing a multiway pipe according to the present invention.
FIG. 4 is a partial cross-sectional front view showing a structure of an example of a rocker shaft using the multiway pipe of the present invention.
[Explanation of symbols]
Reference Signs List 10 Multi-way pipe 11a, 11b, 11c Internal space 12a, 12b, 12c Single pipe T Joining section A Arc section 20 Rocker shaft 21a, 21b Plug

Claims (1)

A cylindrical tube having a plurality of internal spaces that are partitioned from each other and that extend along an axis,
A plurality of single pipes each having a single internal space, a part of the outer peripheral surface of these single pipes, forming a joint portion that is in surface contact with a part of the outer peripheral surface of another single pipe, In addition, the remaining portion of the outer peripheral surface of the single tube is combined with the remaining portion of the outer peripheral surface of another single tube to form a cylindrical outer peripheral surface, and is brought into surface contact with the plurality of single tubes. A tube for a rocker shaft of an internal combustion engine, wherein the tube is formed by welding or brazing joint portions.

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