JPH0569068A - Manufacture of pipe ring for casting - Google Patents

Abstract

PURPOSE:To particularly improve the workability of residue removal, straightening and caulking, to reduce pieces of the parts and to easily and precisely manufacture a pipe ring for casting as the whole body. CONSTITUTION:A long pipe material 1 is cut to the prescribed short length and at the one end, a male joint 4 or a female joint 5 is machined to form the short length pipe materials 6A, 6B. Successively, the inner parts of these short length pipe materials 6A, 6B are cleaned to remove the residue and then the short length pipe materials 6A, 6B are bent to a semi-circular shape or a circular shape one by one at the room temp. to form the ring materials 7A, 7B. Further, these ring materials 7A, 7B are combined as circular shape by connecting the straight end part 3 and the male joint 4 or the female joint 5, and each joint part is caulked while straightening and these are integrally connected. By this method, the residue in the inner part of the pipe material is perfectly removed only at one time of the first cleaning of the pipe ring 8, and by bending this material without developing the twisting, etc., one by one, the straightening and the caulking under the circular condition, are stably and firmly executed and the pipe ring can be suitably manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting pipe ring for use in a cooling liquid passage or the like, which is placed and installed inside a piston or cylinder block of a vehicle engine when it is cast. Regarding the method.

[0002]

2. Description of the Related Art In recent years, with respect to a vehicle engine, development has been made to reduce the size and weight of the engine body and increase the engine output to improve power performance, fuel efficiency and the like. In this high-power engine, the combustion temperature in the combustion chamber inevitably rises, and the heat load on the cylinder block and piston increases, and it is necessary to strengthen the cooling performance against the heat load on the piston that is moving at high speed. Is becoming Therefore, as a measure to strengthen the cooling performance of such a piston,
It has been proposed to cast a pipe ring inside a piston to form an oil gallery and forcibly supply oil to the oil gallery to cool the piston. For this reason, it is required to manufacture a casting pipe ring that copes with this cooling means at low cost and with high accuracy.

A conventional manufacturing method for manufacturing the above casting pipe ring will be described below. The conditions required to manufacture such a pipe ring are that it is easy to process the pipe material into a closed ring shape by a method that enables mass production, and to adjust it to a predetermined dimension when formed into a ring. Is. Also, since the pipe ring is heated to a high temperature when it is cast and installed during casting of the piston, if there are residues of water, oil, etc. inside, they will be discharged as gas during casting and damage the casting. U Therefore, the inside of the pipe ring is washed to completely remove these residues.

Therefore, first, a long pipe material is manufactured by drawing, and the long pipe material is subjected to primary cleaning and subjected to heat treatment such as annealing so as to be easily bent, and then bent into a coil shape. .. Then, the coiled pipe material is cut into a predetermined length to form a ring material, and the ring material is secondarily washed with caustic soda to remove oil during the heat treatment, and further thirdly washed with water. And heat to completely remove the water inside. After that, the clip manufactured in another sub-process is attached to the joint of the ring material, the pipe ring is manufactured by crimping the clip while correcting the twisting of the coil habit of the ring material, and further heating at the same high temperature as during casting. Finally, the internal residue is removed.

[0005]

By the way, in the above-mentioned conventional method for manufacturing a casting pipe ring, since a long pipe material is bent into a coil shape, there is an advantage that the ring material can be easily mass-produced. However, the internal cleaning becomes insufficient, and therefore, it is necessary to clean and heat again with caustic soda or water after cutting the ring material, which increases the number of work steps for removing residues. Further, since the coiled one is cut, it is difficult to make the length accuracy constant, and since the twist is large, the correction becomes very troublesome and the caulking becomes unstable. Further, since the seam of the ring material is crimped by the clip, there are problems such as an increase in the number of parts.

The present invention has been made in view of this point, and particularly improves the workability of residue removal, straightening, and caulking, reduces the number of parts, and facilitates and accurate manufacture of a casting pipe ring as a whole. The purpose is to do.

[0007]

To achieve the above object, the present invention forms a short pipe material by cutting a long pipe material into a predetermined short length and processing a male joint or a female joint at one end. Then, the inside of this short pipe material is washed to remove the residue, and then each short pipe material is bent at room temperature into a semi-circular or circular shape to form a ring material. A pipe ring is manufactured by combining parts in a circular shape by connecting a male joint or a female joint and crimping and integrally connecting the joint parts while straightening.

[0008]

According to the above-mentioned manufacturing method, first, the short pipe material is cut and then bent at room temperature, so that the residue inside the pipe material is completely removed by only the first washing, and the pipes are bent one by one. Since twisting or the like does not occur due to processing, straightening and crimping in a circular state can be performed stably and firmly, and an optimal pipe ring can be manufactured.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a manufacturing process suitable for carrying out the present invention will be described. First, in step (1), by drawing, for example, the diameter is 8 mm and the wall thickness is 0.5 m.
m, a long pipe material 1 made of hollow aluminum with a length of 3000 mm is manufactured, and the long pipe material 1 is cut in a step (2) into a length of about half of a pipe ring product, for example, 100 mm. To form the short pipe material 2. Then, in step (3), one end of one short pipe material 2 has a straight end portion 3 at one end thereof and a male joint 4 having a small diameter corresponding to the wall thickness at the other end, and the same straight end portion 3 at one end of the other short pipe material 2. At the other end, a female joint 5 having a large diameter corresponding to the wall thickness is machined to a predetermined length required for caulking, and two types of short pipe materials 6A, 6B
To form. In the step (4), the insides of these two types of short pipe materials 6A and 6B are washed with caustic soda or the like and heated, and the residues of oil and the like remaining inside the pipe materials during the drawing, cutting and stretching are Remove in a short length and straight pipe. Then, in the step (5), the above-mentioned two types of short pipe materials 6A and 6B are processed into a special bending machine 1
Bending is performed in a semicircular shape one by one using 0 to form two types of semicircular ring members 7A and 7B.

The bending machine 10 has, for example, as shown in FIG. 2, two pressing rollers 12 and 13 fixed to the fixed side by metal fittings 11 at predetermined intervals. A circular mold roller 14 is provided in the middle so as to be vertically movable. As a result, when one short pipe material 6A is bent, the short pipe material 2 and the die roller 14 are positioned so that their centers coincide with each other, and the short pipe material 2 is horizontally placed on the two pressing rollers 12 and 13. It is mounted, and in this state, the mold roller 14 is pressed and moved downward. Then, as the mold roller 14 is pressed, the pressing rollers 12 and 13 are pressed.
Is rolled and the short pipe material 2 is bent while being bent in a U shape, and at this time, the short pipe material 2 is pushed back by the pressing rollers 12 and 13 while shifting the pressing points from the center side to both end sides. Thus, by the pressing action of the mold roller 14 and the pressing rollers 12 and 13 in the opposite radial directions,
The short pipe 2 and the male joint 4 of the short pipe material 6A are automatically bent into a semicircular ring material along the die roller 14 while keeping the hollow state. The semi-circular ring material 7A in this case is almost semi-circular due to the shape of the die roller 14, but both ends are slightly open, which will be corrected in a later step.

The other short pipe material 6B is also the short pipe 2
And the female joint 5 have the same mold roller 14 and pressing rollers 12, 1
3, the semi-circular ring material 7B is automatically bent by the pressing movement of the die roller 14 below. Here, since each short aluminum product is simply bent into a semicircle, it is not necessary to perform heat treatment or the like, and therefore it is possible to perform processing at room temperature. As a result, the insides of the semicircular ring members 7A and 7B are maintained in the initial cleaning state, and it is not necessary to clean again after this processing. In this way, the two types of semi-circular ring materials 7A and 7B are automatically mass-produced one by one with a clean inside.

Then, in the final step (6), two kinds of semicircular ring members 7A and 7B are attached to the straight end portions 3 of both members.
Are inserted into the male joint 4 and the female joint 5, respectively, to connect the short pipes 2 and 2, so that they are combined into one closed circular ring shape. At this time, a relatively large fitting adjustment area is generated at the two joint portions on the circumference, which allows the two types of semicircular ring members 7A and 7B to be easily and surely formed even if both ends are open. Can be combined into a circular shape of a book. In addition, since the semicircular ring members 7A and 7B maintain a clean state in the initial cleaning, the residue removing process is not necessary and the caulking work is immediately performed. Then, the straight end 3 and the male joint 4 and the straight end 3 and the female joint 5 are inserted into the male joint while correcting the open shape of the insertion portion into a circular shape and setting the inner diameter to a predetermined size. 4 and the female joint 5 are simultaneously caulked and integrally connected, and thus one hollow circular casting pipe ring 8 is manufactured without any residue inside.

3 (a) and 3 (b), as an application example of the casting pipe ring 8 manufactured as described above,
The case of casting into a piston will be described. Reference numeral 20 is a piston manufactured by casting an aluminum alloy, and a head 21 is continuously provided with a circular cylindrical skirt 22.
A plurality of grooves 24 for mounting a piston ring are formed on the outer periphery of the thick portion 23 on the first side, and the boss portion 2 in the middle of the skirt 22 is formed.
5 is provided with a pin hole 26. Therefore, when the piston 20 is cast, the pipe ring 8 is inserted and installed inside the mold to inject the molten aluminum alloy S. Then, at this time, the pipe ring 8 is heated by the aluminum alloy S which is melted at a high temperature, but since the internal residue is removed and no gas is generated, the pipe ring 8 is favorably cast. Also, since the pipe ring 8 is a combination of semi-circular pipes, even if it thermally expands, it expands concentrically, and even if there is a slight gap between the male joint 4 and the female joint 5 on the circumference, It is closed by the alloy S, and thus the pipe ring 8 is coaxially housed and integrally cast in the thick portion of the piston on the head 21 side. An oil gallery 27 is formed by the pipe ring 8 and the oil gallery 2 is formed.
By circulating the oil through 7, the piston 20 is forcibly cooled when the engine is operating.

Another embodiment of the present invention will be described with reference to FIG. (A) is a female joint 5 at one end of the short pipe material 2.
Only one type of semi-circular ring material 7 is formed by processing only one, and two semi-circular ring materials 7 of one type are combined in a circular shape by connecting the straight end 3 and the female joint 5. .. (B) shows that one type of semi-circular ring material 7'is formed by processing only the male joint 4 at one end of the short pipe material 2, and the two semi-circular ring materials 7'of one type are straight end portions. 3 and the male joint 4 are connected to form a circular combination. In these examples, the strength of the caulking is slightly reduced by one type of joint 4 or 5, but the hollow circular casting pipe ring 8 can be similarly produced without any residue inside, and It has the advantage that a semicircular ring material 7 or 7'is sufficient.

Another embodiment of the present invention will be described with reference to FIG. In this embodiment, for example, a female joint 5 is attached to one end of a short pipe material 2'having a length twice that of the above case.
Is processed and bent into a substantially closed circle by a special bending machine to form a circular ring material 9. Then, the straight end portion 3 of the circular ring material 9 and the female joint 5 are connected and caulked, whereby the casting pipe ring 8 is similarly manufactured. In this embodiment, since it is formed on the circular ring material 9, straightening and caulking operations are easy, but the structure of the bending machine becomes complicated. Incidentally, also in this embodiment, it goes without saying that a male joint or a male joint and a female joint can be used.

Although the embodiment of the present invention has been described above, the present invention is not limited to this.

[0017]

As described above, according to the present invention,
In the production of casting pipe rings, the removal of internal residues is emphasized. First, the short pipe material is cut and then bent at room temperature, so the internal residues can be completely removed by only the first washing. Therefore, the cleaning work process is greatly simplified. Since the ring members are formed one by one by bending with a bending machine, the ring members can be straightened and crimped stably and firmly without twisting or the like. Since the male joint and the female joint are preliminarily processed on the short pipe, the number of parts is reduced, and in the case of forming the semicircular ring material, the circular combination can be easily and surely performed. In the embodiment in which the semi-circular ring material is formed, bending is easy, and in the embodiment in which the circular ring material is formed, straightening and crimping are easy. Since the bending machine is configured to press and move the die roller against the two pressing rollers to automatically perform processing, the productivity is good.

[Brief description of drawings]

FIG. 1 is a process drawing showing a cross section of a manufacturing process suitable for carrying out a method for manufacturing a casting pipe ring according to the present invention.

FIG. 2 is a schematic view showing an embodiment of a bending machine for a short pipe material.

FIG. 3 shows a state where a casting pipe ring according to the present invention is cast into a piston, and (a) is a longitudinal sectional view,
(B) is a horizontal sectional view.

FIG. 4 shows another embodiment of the present invention,
Both (a) and (b) are sectional views of a casting pipe ring.

FIG. 5 is a sectional view of a casting pipe ring according to still another embodiment of the present invention.

[Explanation of symbols]

 1 long pipe material 2 short pipe material 3 straight end 4 male joint 5 female joint 6A short pipe material 6B short pipe material 7 ring material 7'ring material 7A ring material 7B ring material 8 pipe ring 9 ring material

Claims (4)

[Claims] 1. A long pipe material is cut into a predetermined short length, and a male or female joint is processed at one end to form a short pipe material, and then the inside of this short pipe material is washed to remove residues. Remove and then bend each short pipe at room temperature into a semicircle or circle to form a ring, and then combine this ring into a circle by connecting a straight end and a male or female joint. A method for manufacturing a casting pipe ring, which comprises manufacturing the pipe ring by crimping and integrally connecting the joint portions while straightening. 2. The short pipe has two types in which a male joint and a female joint are processed separately, and these two types of short pipes are respectively bent into semicircles to form two types of semicircular ring members, The method for producing a casting pipe ring according to claim 1, wherein the two types of semi-circular ring materials are connected in a straight end portion to a male joint and a female joint, respectively, and are combined in a circular shape. 3. The casting pipe ring according to claim 1, wherein the short pipe is formed in one type having a straight end portion at one end and one of a male joint and a female joint at the other end. Manufacturing method. 4. The bending material is a bending machine composed of two pressing rollers and a die roller movably provided in the middle between the pressing rollers, and is bent into a semi-circular shape or a circular shape. Item 2. A method for manufacturing a casting pipe ring according to Item 1.