JPH0489141A - Method and device for bulging plural projecting parts of pipe - Google Patents

Abstract

PURPOSE:To bulge >=3 pieces of projecting parts at prescribed intervals along the axial direction of a pipe by first forming the projecting parts of the extreme central zone, then successively forming the projecting parts in one zone exclusive of the extreme central zone by each one zone from the extreme central zone toward both ends of the pipe. CONSTITUTION:The two projecting parts 104A of the extreme central zone 105 are first formed. The two projecting parts 104B of the 2nd band 106 adjacent to the outer side of the extreme central zone 105 are then formed. Further, the two projecting parts 104c in the band 107 on the outermost side adjacent to the outer side of the 2nd band 106 are formed. The projecting parts 104A, 104B, 104C of the large height size are bulged at the prescribed intervals at 6 points along the axial direction of the pipe 101 in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for bulging a plurality of convex portions of a pipe.

[Prior Art] Pipes are used in various parts of automobiles, such as exhaust pipes, internal structures of mufflers, exhaust manifolds, and intake pipes. This pipe is sometimes used without any processing, but it is also used with various processing such as pipe expansion and burring, or by welding parts such as branch pipes and brackets to it. be done.

For example, as shown in FIG. 13, when forming a large number of burring holes 102 at predetermined intervals along the axial direction of a pipe 101, a burring hole drilling process is usually adopted. .

Furthermore, as shown in FIG. 14, when two large-height branch pipes 103 are made to protrude from the pipe 101 at a predetermined interval along its axial direction, for example, by bulge forming, After forming the convex portion, a hole is formed at the top of the convex portion. The reason why the number of branch pipes 103 that protrude from the pipe 1°1 is limited to two is that even if you try to make a large number (three or more) of protrusions protrude from the pipe 101, the central part of the pipe 103 is limited to two. It is difficult for the material to enter the protrusions (this is because the thickness of the protrusions decreases, making it difficult to ensure quality).

[Problems to be Solved by the Invention] However, as shown in FIG.
In the case where branch pipes 103 with large height dimensions are to be protruded at multiple locations (three or more locations) at predetermined intervals along the axial direction (for example, branches of an exhaust manifold attached to the cylinder block of an engine). When attempting to form a pipe), as mentioned above, the purling hole drilling process does not allow for a large height dimension, making it difficult to form the pipe. In addition, in bulge forming, the number of branch pipes 103 is limited to two or less, and it has been difficult to form them using conventional burring hole drilling and bulge forming processes. In addition, the pipe 101 in FIG.
As shown in FIG.
After molding 04, the top 114 of the convex portion 104 is formed to form a hole.

The present invention has been made in order to solve the above-mentioned problems, and its purpose is to provide a pipe with protrusions made of branch pipes particularly large in height at predetermined intervals along the axial direction of the pipe. It is an object of the present invention to provide a method for bulge forming a plurality of convex portions of a pipe and an apparatus therefor, which can perform bulge forming at three or more locations.

[Means to solve the problem]

In order to achieve the above object, the invention according to claim 1 is a method in which three or more convex portions are bulge-molded on a pipe at predetermined intervals along the axial direction of the pipe, and these convex portions are Centering on the most central zone consisting of one or two convex portions, one or more convex portions are arranged symmetrically toward both ends of the pipe in units of bands consisting of a pair of convex portions located symmetrically on both sides of the most central zone. It is divided into bands, and the convex part of the most central band is formed first, and then the convex parts in one band other than the most central part are formed one by one from the most central band toward both ends of the pipe. It is something that is formed individually.

In the invention according to claim 1, bulge forming is performed by setting a pipe in a pipe hole formed by two molds constituting a bulge mold, and setting the pipe in one bulge mold. It can be done in the process (
invention according to claim 2).

The invention according to claim 3 is characterized in that three or more convex portions are bulge formed on the pipe at predetermined intervals along the axial direction of the pipe, and from one or two of the convex portions. When dividing the pipe into one or more bands symmetrically toward both ends of the pipe, the convex part of the most central belt A bulge forming mold for the first step consists of a two-part mold in which a recess with a shape corresponding to that of A mold for use after the first step consisting of a two-split mold in which a concave portion having a shape corresponding to the convex portion in at least one outer band is formed, and a hole for a pipe is formed in communication with the concave portion to set a pipe. It is equipped with a bulge mold.

The invention as set forth in claim 4 provides a pressure medium to be applied to the pipe along its axial direction by introducing a pressure medium into the pipe set in the pipe hole formed by the two-split mold forming the bulge mold. 3 or more convex parts separated by a predetermined interval
Bulge forming is performed using two bulge forming molds, and the unit is a band consisting of a pair of convex parts located symmetrically on both sides of the centralmost band consisting of one or two convex parts among the above convex parts. When the pipe is divided into one or more bands symmetrically toward both ends of the pipe, a concave portion of a shape corresponding to one or two convex portions of the centralmost zone is formed in the mold, and a concave portion of the shape corresponding to one or two convex portions of the centralmost zone is formed in the mold. A cylinder portion communicating with the pipe hole is provided in each of the portions corresponding to the convex portions, and inside the cylinder portions, there is provided a cylinder portion that is moved forward to the position of the outer peripheral surface of the pipe or to a retracted position corresponding to the top of the convex portion. A retracting piston is provided, and when forming the convex part of the most central band, this piston is placed in a forward position with respect to the part corresponding to the convex part of the band other than the most central band, and when forming the convex part of the most central band, When the convex part of the band is not formed, the part corresponding to the convex part of the band is placed in the forward position, and when the convex part of the band other than the most central band is formed, and after forming, the part is placed in the retreat position. It has the means.

In the invention set forth in claim 4, the piston may have an abutment surface shaped to match the outer peripheral surface of the pipe (invention set forth in claim 5).

The invention as set forth in claim 6 provides a pressure medium to be applied to the pipe along its axial direction by introducing a pressure medium into the pipe set in the pipe hole formed by the two-split mold constituting the bulge mold. 3 or more convex parts separated by a predetermined interval
Bulge forming is performed using two bulge forming molds, and the unit is a band consisting of a pair of convex parts located symmetrically on both sides of the centralmost band consisting of one or two convex parts among the above convex parts. When the pipe is divided into one or more bands symmetrically toward both ends of the pipe, a concave portion of a shape corresponding to one or two convex portions of the centralmost zone is formed in the mold, and a concave portion of the shape corresponding to one or two convex portions of the centralmost zone is formed in the mold. A first cylinder portion that communicates with the pipe hole is provided in each of the portions corresponding to the convex portions, and the first cylinder portion is moved forward to the position of the outer peripheral surface of the pipe or to a predetermined retreat position. A first piston that retracts is provided in the mold, and a second cylinder portion is provided in the mold so as to communicate with each of the first cylinder portions. A second piston is provided that moves parallel to the inside and outside of the first cylinder part and advances to a forward position corresponding to the top of the convex part of a band other than the most central band of the pipe or retreats out of the first cylinder part. , when forming the convex part of the most central band, this first piston is positioned in a forward position with respect to the part corresponding to the convex part of the band other than the most central band, and when forming the convex part of the most central band, When the convex part of the band is not formed, the part corresponding to the convex part of the band is located in the forward position, and when forming the convex part of the band other than the most central band and after forming, the part is positioned in the predetermined retreat position, On the other hand, the second piston is provided with a control means that causes the second piston to move backward when the first piston is moving forward, and to move the second piston forward when the first piston is moving backward.

In the invention set forth in claim 6, the second piston may have a flat surface on which the top of the convex portion is formed (the invention set forth in claim 7).

[For production]

In the invention according to claim 1, the convex portion of the most central zone is first formed, and then the convex portion of one zone other than the most central zone is formed into one band from the most central zone toward both ends of the pipe. three or more convex portions are bulge formed on the pipe at predetermined intervals along the axial direction of the pipe.

In the invention set forth in claim 2, bulge forming is performed in the same manner as in the invention set forth in claim 1, but the pipe is set in the pipe hole formed by the two halves of the bulge forming mold, and Bulge forming is performed in one step, which consists of setting the pipe in two bulge forming molds.

In the invention according to claim 3, the convex portion of the centralmost zone of the pipe is first formed by the bulge mold for the first step, and then the convex portion of the centralmost zone of the pipe is formed by the bulge mold for the first and subsequent steps. The convex portions in one band are formed one after another in each band from the centermost band toward both ends of the pipe.

In the invention as set forth in claim 4, the convex portion in the centermost zone of the pipe is first formed using one bulge forming die. At this time, the control means positions the piston at an advanced position with respect to the portion corresponding to the convex portion of the band other than the most central band. As a result, the convex portions in the bands other than the most central zone are not formed, and the material of the pipe flows smoothly into the convex portions in the most central zone of the pipe.

Next, convex portions in one band other than the most central band are formed one after another for each band from the most central band toward both ends of the pipe. At this time, the control means positions some of the pistons in the forward position with respect to portions corresponding to the protrusions of the bands other than the centralmost band when the protrusions of the bands are not formed. As a result, the convex part in the band is not formed,
The material made of the pipe flows smoothly into the convex portions to be formed in the bands other than the centralmost band.

Also, some of the pistons are located in the retracted position when forming the convex portions of bands other than the most central band and after forming. The material made of the pipe flows smoothly into the convex portions to be formed in the bands other than the centralmost band.

In the invention set forth in claim 6, the same effect as in the invention set forth in claim 4 occurs, but during bulge forming, the second piston advances to the forward position corresponding to the top of the convex part of the band other than the most central band. Therefore, the top of the convex portion is molded into a shape that matches the second piston.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a bulge forming apparatus according to the present embodiment, and a convex portion 104A having a large height dimension is provided on a pipe 101 shown in FIG. 12 at a predetermined interval along the axial direction.
104B and 104C are bulged in six locations.

The bulge forming device 1 consists of an upper mold 2 and a lower mold 3 that can be separated and combined.
It has one bulge mold 4 consisting of. Upper mold 2.
The lower die 3 has a pipe hole 5 into which the pipe 101 is set.
is formed.

Both end surfaces 1 of the pipe 101 are provided on both end sides of the vibrator hole 5.
A pair of molding punches 6°6 that come into contact with 01A and 10IA and compress the pipe 101 in the axial direction are inserted into the vibrator hole 5.
It is arranged so that it can be inserted and removed freely. A shaping water nozzle 6A is formed in one of the shaping punches 6.

The pair of convex portions 104A, 104B, 1 shown in FIG.
Among 04C, the most central zone 1 consisting of two convex portions 104A
When dividing the pipe into one or more bands 106 and 107 symmetrically toward both ends of the pipe, with the band consisting of a pair of protrusions located symmetrically on both sides of the pipe as a unit, as described later, the centralmost band The two convex portions 104A of 105 are first molded,
Next, a second band 10 adjacent to the outside of the centralmost band 105
The two convex portions 104B at 6 are molded, and the two convex portions 104C at the outermost band 107 adjacent to the outside of the second band 106 are further molded. Concave portions 7, 7 having shapes corresponding to the two convex portions 104A, 104A of 105 are formed.

Then, a second band 10 adjacent to the outside of the centralmost band 105
Vertical cylinder portions (first cylinder portions) 8, 8 are provided in portions corresponding to the convex portions 104B, 104B in 6, and these vertical cylinder portions 8°8 are connected to the pipe hole portion 5, respectively. There is.

Also, the outermost band 10 adjacent to the outside of the second band 106
A vertical cylinder portion (first cylinder portion) 9.9 is provided at a portion corresponding to the convex portions 104C, 104C in 7, and this cylinder portion 9.9 is connected to the vibrator hole 5, respectively.
is connected to.

In each vertical cylinder part 8, a vertical piston (first piston) 10 that moves perpendicularly to the axis of the pipe 101 and advances to the position of the outer circumferential surface 101B of the pipe 101 or retreats to a predetermined retreat position. is provided.

A vertical piston 11 is provided in each vertical cylinder part 9, which moves at right angles to the axis of the pipe 101 and advances to the position of the outer peripheral surface 101B of the pipe 101 or retreats to a predetermined retracted position. Vertical piston 10.11
Contact surfaces 10A and IIA having a shape that matches the outer circumferential surface 101B of the pipe 101 are formed at the tip of the pipe 101.

Inside the upper mold 2, horizontal cylinder portions (second cylinder portions) 12.1 are provided in communication with the respective vertical cylinder portions 8.8, respectively.
2 is provided. Additionally, horizontal cylinder portions (second cylinder portions) 13.13 are provided in the upper die 2 at portions corresponding to the respective vertical cylinder portions 9.9.

A horizontal piston 14 (second piston) is provided in each horizontal cylinder portion 12, and a horizontal piston 15 (second piston) is provided in each horizontal cylinder portion 13.

The horizontal piston 14.15 has flat surfaces 14A and 15A on which the tops of the convex parts 104B and 104C are formed, and moves in parallel to the inside and outside of the horizontal cylinder part 12.13 with respect to the axis of the pipe 101. or the horizontal cylinder portion 12
．． 13 Retreat outside.

By means of control means (not shown), the above-mentioned vertical piston 10
．． 11 and horizontal pistons 14, 15 are controlled as follows.

That is, as shown in FIG. 2, when forming the two convex portions 104A of the most central zone 105, the vertical pistons 10 and 11 move the convex portions 104B and 104C of bands other than the most central zone 105.
It is located in the forward position with respect to the portion corresponding to (shown in FIG. 12).

Further, as shown in FIG. 3, the vertical piston 10 is located at the retracted position after forming the two convex portions 104A of the centralmost band 105, and the vertical piston 11 is located at the forward position. The horizontal piston 14 is moving forward when the vertical piston 10 is moving backward, and the horizontal piston 15 is moving forward when the vertical piston 10 is moving backward.
is moving backwards when it is moving forward.

Further, as shown in FIG. 4, the vertical piston 10.11
is in the retracted position, and the horizontal pistons 14 and 15 are in the forward position.

In addition, 16A and 16B in FIG.
Molding completion detection sensors 17A and 17B for the centralmost band detect molding of the two convex portions 104A; second band molding completion detection sensors 18A detect molding of the two convex portions 104B of the second band 106; 18B is a position detection sensor that detects the retracted position of the horizontal piston 15, and signals from each sensor are transmitted to the control means.

A pressure medium made of liquid is then pumped into the inside of the pipe 101, and the pipe 101 is compressed in the axial direction to form a bulge as described below.

As shown in FIG.
4A is molded first. The convex portion 104A matches the shape of the concave portion 7. In this case, the control means cause the vertical piston 10.11 to move around the zones 106.10 other than the central zone 105.
7 convex portion 104B.

It is located in the forward position with respect to the portion corresponding to 104C. As a result, the bands 106.10 other than the centermost band 105
The convex portions 104B and 104C at 7 are not formed, and the material of the pipe 101 flows smoothly into the two convex portions 104A of the centralmost zone 105 of the pipe 101.

Next, as shown in FIG. 3, the two convex portions 104B of the second band 106 adjacent to the outside of the centermost band 105 are formed. During bulge forming, each horizontal piston 14
Since the band 106 has moved forward to the forward position corresponding to the tops of the two protrusions 104B, the tops of the protrusions 104B are pressed against and shaped by the flat surface 14A of the horizontal piston 14, and the tops of the protrusions 104B are Formed flat.

At this time, the control means causes the vertical piston 11 to be located in the forward position with respect to the portion corresponding to the two protrusions 104C of the outermost band 107 when the two protrusions 104C of the outermost band 107 are not formed. ing.

As a result, the two convex portions 10 on the outermost band 107
4C is not formed, and 2 of the second band 106 is to be formed.
The material made of the pipe 101 flows smoothly into the two convex portions 104B.

Further, as shown in FIG. 4, two convex portions 104C in the outermost band 107 adjacent to the outside of the second band 106
is formed. During bulge forming, each horizontal piston 15
has moved forward to the forward position corresponding to the tops of the two convex portions 104C of the outermost band 107, the tops of the convex portions 104C are pressed against the flat surface 15A of the horizontal piston 15, and the convex portions 104C The top is flat.

At this time, since the two convex portions 104A of the central band 105 and the two convex portions 104B of the second band 106 have already been formed by the control means, the two convex portions 1 of the outermost band 107
The material made of pipe 101 flows smoothly into 04C.

In this way, convex portions 104A, 104B, and 104C with large height dimensions are bulge-formed at six locations on the pipe 101 shown in FIG. 12 at predetermined intervals along the axial direction. These protrusions can be used as they are, or can be used as branch pipes by drilling holes in the tops of the protrusions.

According to the above configuration, first, convex portions 104A, 104B, and 104C having large height dimensions are bulge-formed at six locations on the pipe 101 at predetermined intervals along the axial direction of the pipe 101. be able to.

Second, in one process consisting of a pipe set in one bulge forming mold 4, bulge forming can be performed continuously over six locations of the convex portions 104A, 104B, and 104C having large height dimensions. . In this case, this convex portion 104A,
104. B, the top of 104C can be formed into a flat shape.

Thirdly, since only one bulge mold 4 is required, the required number of bulge molds 4 can be minimized.

In this embodiment, abutment surfaces 10A and IIA having a shape that matches the outer peripheral surface 101B of the pipe 101 are formed at the tip of the vertical piston 10.11, but the tip of the vertical piston 10.11 is It is not limited to such a shape.

Further, in this embodiment, the horizontal pistons 14 and 15 have flat surfaces 1 on which the tops of the convex portions 104B and 104C are formed.
4A and 15A, but the shape is not limited to this, and the surface can have various shapes.

Further, in this embodiment, a liquid is used as the pressure medium that is pumped into the inside of the pipe 101, but the pressure medium is not limited to liquid, and for example, rubber, powder, etc. can also be used. .

In this embodiment, a case has been described in which six convex portions 104A, 104B, and 104C are formed on the pipe 101, but the number of convex portions is not limited to six, and three or more convex portions may be formed. It can be applied when molding is attempted. In this case, if the number of convex parts is odd,
The number of convex portions in the most central zone is one. When the number of convex portions is an even number, the number of convex portions in the most central zone is two.

5 to 8 show a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a second embodiment of the present invention.

In FIG. 5, reference numeral 21 denotes a bulge forming apparatus according to the present embodiment, and a convex portion 104A having a large height is formed on the pipe 101 shown in FIG. 12 at a predetermined interval along the axial direction.
, 104B, and 104C are bulge-formed at six locations.

The bulge forming device F21 includes an upper mold 22 that can be freely separated and combined;
It has one bulge mold 24 consisting of a lower mold 23. Upper mold 22. A pipe hole 25 into which the pipe 101 is set is formed in the lower mold 23 .

At both ends of the pipe hole 25, a pair of shaping punches 26 and 26 are inserted into and pulled out of the pipe hole 25 to compress the pipe 101 in the axial direction by contacting both end surfaces 101A and 10IA of the pipe 101. They are freely placed. A molding water nozzle 26A is formed in one of the molding push bunches 26.

The pair of convex portions 104A, 104B, 1 shown in FIG.
Among 04C, the most central zone 1 consisting of two convex portions 104A
When the pipe is divided into one or more bands 106 and 107 symmetrically toward both ends of the pipe, with a band consisting of a pair of convex portions located symmetrically on both sides of the pipe as a unit, as described later, the centralmost band The two convex portions 104A of 105 are first molded,
Next, a second band 10 adjacent to the outside of the centralmost band 105
The two convex portions 104B at 6 are molded, and the two convex portions 104C at the outermost band 107 adjacent to the outside of the second band 106 are further molded. Recesses 27, 27 having shapes corresponding to the two projections 104A, 104A of 105 are formed.

Then, a second band 10 adjacent to the outside of the centralmost band 105
Vertical cylinder portions 28.28 are provided in the portions corresponding to the convex portions 104B, 104B in 6, and these vertical cylinder portions 28.28 communicate with the pipe holes 25, respectively. Further, vertical cylinder portions 29.29 are provided in portions of the outermost band 107 adjacent to the outside of the second band 106 that correspond to the convex portions 104C, 104C, and these cylinder portions 29.29 each have pipes. Hole 25
is connected to.

Inside each vertical cylinder part 28 is a vertical piston 30 that moves perpendicularly to the axis of the pipe 101 and advances to the position of the outer peripheral surface 101B of the pipe 101 or retreats to a retracted position corresponding to the top of the convex part 104B. is provided.

In each vertical cylinder part 29, a vertical piston 31 moves perpendicularly to the axis of the pipe 101 and advances to the position of the outer peripheral surface 101B of the pipe 101 or retreats to a retracted position corresponding to the top of the convex part 104C. is provided. At the tips of the vertical pistons 30 and 31, there are contact surfaces 30A and 31A having a shape that matches the outer peripheral surface 101B of the pipe 101.
is formed.

Control means (not shown) control the vertical piston 30 as described above.
．． The sequence of 31 is controlled as follows.

That is, as shown in FIG. 6, when forming the two convex portions 104A of the most central zone 105, the vertical pistons 30, 31 are located at portions corresponding to convex portions 104B and 104C of bands other than the most central zone 105. is located in the forward position relative to the

Further, as shown in FIG. 7, the vertical piston 3° is in the retracted position after forming the two convex portions 104A of the centralmost band 105 and when forming the two convex portions 104B of the second band 106. However, the vertical piston 31 is located at the forward position.

Furthermore, as shown in FIG.
are located in the retracted position after the two convex portions 104B of the second band 106 are formed and when the two convex portions 104C of the outermost band 107 are formed.

In addition, 32A and 32B in FIG.
Forming completion detection sensors 33A and 33B for the centralmost band detect forming of the two convex portions 104A; second band forming completion detection sensors 34A and 33B detect forming of the two convex portions 104B of the second band 106; 34B is an outermost molding completion detection sensor that detects the molding of the two convex portions 104C of the outermost band 107, and signals from each sensor are transmitted to the control means.

A pressure medium made of liquid is then pumped into the inside of the pipe 101, and the pipe 101 is compressed in the axial direction to form a bulge as described below.

As shown in FIG.
4A is molded first. The convex portion 104A matches the shape of the concave portion 27. In this case, the control means cause the vertical pistons 30 .
07 convex portion 104B.

It is located in the forward position with respect to the portion corresponding to 104C. As a result, the bands 106.10 other than the centermost band 105
The convex portions 104B and 104C at 7 are not formed, and the material of the pipe 101 flows smoothly into the two convex portions 104A of the centralmost zone 105 of the pipe 101.

Next, as shown in FIG. 7, the two convex portions 104B of the second band 106 adjacent to the outside of the centralmost band 105 are formed. At that time, the control means causes the vertical piston 31 to:
When the two convex portions 104C of the outermost band 107 are not formed, the portion of the band 107 corresponding to the two convex portions 104C is located at the forward position. As a result, the two convex portions 104C on the outermost band 107 are not formed, and the two convex portions 104B on the second band 106 are not formed.
The material made of the pipe 101 flows smoothly.

Further, as shown in FIG. 8, two convex portions 104C in the outermost band 107 adjacent to the outside of the second band 106
is formed. Due to the control means, the vertical piston 30.31 is then located in the retracted position. Therefore, the pipe 10 can be smoothly attached to the two convex portions 104C of the outermost band 107.
A material consisting of 1 flows.

In this way, convex portions 104A, 104B, and 104C with large height dimensions are bulge-formed at six locations on the pipe 101 shown in FIG. 12 at predetermined intervals along the axial direction. These protrusions can be used as they are, or can be used as branch pipes by drilling holes in the tops of the protrusions.

According to the above configuration, the same effects as the first and third effects of the first embodiment can be achieved, and in one process consisting of setting a pipe in one bulge forming mold 24, continuous Convex portions 104A, 104B, 10 with large height dimensions
4C can be bulge-formed at six locations. In this case, the convex portions 104A, 104B, 104
Cf7) The top can be formed into a curved shape.

In this embodiment, contact surfaces 30A and 31A having a shape that matches the outer peripheral surface 101B of the pipe 101 are formed at the tips of the vertical pistons 30 and 31, but the tips of the vertical pistons 30 and 31 are It is not limited to such a shape.

Further, in this embodiment, a liquid is used as the pressure medium that is pumped into the pipe 101, but the pressure medium is not limited to liquid, and for example, rubber, powder, etc. can also be used. .

Furthermore, in this embodiment, a case has been described in which six convex portions 104A, 104B, and 104C are formed on the pipe 101, but the number of convex portions is not limited to six, and three or more convex portions may be formed. It can be applied when molding is attempted. In this case, if the number of convex parts is odd,
The number of convex portions in the most central zone is one. When the number of convex portions is an even number, the number of convex portions in the most central zone is two.

9 to 11 show a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a third embodiment of the present invention.

9 to 11, the bulge forming apparatus 41 according to the present embodiment includes a convex portion 104A having a large height dimension, which is arranged at a predetermined interval along the axial direction of the pipe 101 shown in FIG. 104B.

104C is bulged in six locations.

The bulge forming device 41 includes a bulge forming mold 42 for the first step shown in FIG. 9, a bulge forming mold 43 for the second step shown in FIG. 10, and a bulge forming mold 43 for the third step shown in FIG. It is composed of a mold 44.

The bulge mold 42 for the first step is an upper mold 45 that can be separated and combined. It has a lower mold 46, and the upper mold 45 has recesses 47, 4.
7 is formed, and the upper mold 45. The lower mold 46 has this recess 47.
, 47, and a pipe hole 48 is formed in which the pipe 101 is set. A pair of shaping punches 49 are provided in the vibrator hole 48 for compressing the pipe 101 in the axial direction by contacting both end surfaces 101A and 10IA of the pipe 101.
49 are arranged so that they can be inserted and extracted freely. A shaping water nozzle 49A is formed in one of the shaping punches 49.

The concave portion 47 is connected to the pair of convex portions 104 shown in FIG.
A, 104B, and 104C, centering on the most central zone 105 consisting of two convex portions, one or more bands are symmetrically located toward both ends of the vibrator, with each band consisting of a pair of convex portions located symmetrically on both sides thereof. When divided into bands, the shape corresponds to the convex portion 104A of the centralmost band 105.

The bulge forming mold 43 for the second step is an upper mold 49 that can be freely separated and combined. It has a lower mold 50, and the upper mold 49 has a centralmost zone 10.
Concave portions 47, 47 corresponding to convex portions 104A, 104A of No. 5
and a concave portion 51 corresponding to the convex portion 104B of the second band 106.
, 51 are formed.

The pipe 10 communicates with this recess 47, 47.51.51.
1 is set in the pipe hole 52 that is set in the upper die 49. Lower mold 5
0. The pipe 1 is inserted into the pipe hole 52.
The pipe 10 is in contact with both end surfaces 101A and 101A of o1.
A pair of shaping punches 53.5 that compress 1 in the axial direction
3 are arranged so that they can be inserted and removed freely. A shaping water nozzle 53A is formed in one of the shaping punches 53.

The bulge mold 44 for the third step is an upper mold 54 that can be freely separated and combined. It has a lower mold 55, and the upper mold 54 has a centralmost zone 10.
Concave portions 47, 47 corresponding to convex portions 104A, 104A of No. 5
, concave portions 51, 51 corresponding to convex portions 104B, 104B of second band 106, and convex portion 104C of outermost band 107.
, 104C are formed.

A pipe hole 57 communicating with the recesses 47, 47, 51, 51, 56.56 and into which the pipe 101 is set is provided in the upper mold 54. It is formed on the lower mold 55.

The pipe hole 57 has both end surfaces 101A of the pipe 101.
, 10IA, a pair of shaping punches 58, 58 that compress the pipe 101 in the axial direction are arranged so as to be freely inserted and withdrawn. A shaping water nozzle 58A is formed in one of the shaping punches 58.

Then, as shown in FIG. 9, the two convex portions 104A of the centralmost band 105 shown in FIG. 12 are formed first.

Next, as shown in FIG. 10, two convex portions 104B of the second band 106 adjacent to the outer side of the centralmost band 105 shown in FIG. 12 are formed.

Furthermore, as shown in FIG. 11, 2 in the outermost band 107 adjacent to the outside of the second band 106 shown in FIG.
Two convex portions 104C are formed.

In this way, convex portions 104A, 104B, and 104C with large height dimensions are bulge-formed at six locations on the pipe 101 shown in FIG. 12 at predetermined intervals along the axial direction. These protrusions can be used as they are, or can be used as branch pipes by drilling holes in the tops of the protrusions.

According to the above configuration, three bulge forming molds 42.4
The three steps of 3.44 produce the same effect as the first effect of the first embodiment.

In addition, since actuators such as pistons are not used in the three bulge molds 42, 43, 44 (an appropriate actuator is not required when connecting/separating the three bulge molds 42, 43, 44). ), the structure of the bulge mold can be simplified.

Note that in this embodiment, a liquid is used as the pressure medium that is pumped into the inside of the pipe 101, but the pressure medium is not limited to liquid, and for example, rubber, powder, etc. can also be used. .

Further, in this embodiment, a case has been described in which six convex portions 104A, 104B, and 104C are formed on the pipe 101, but the number of convex portions is not limited to six, and three or more convex portions may be formed. It can be applied when molding is attempted. In this case, if the number of convex portions is an odd number, the number of convex portions in the most central band is one. When the number of convex portions is an even number, the number of convex portions in the most central zone is two.

〔Effect of the invention〕

As described above, according to the invention according to claim 1,
Bulge-forming can be performed on the pipe at three or more locations with large protrusions at predetermined intervals along the axial direction of the pipe.

According to the invention according to claim 2, in addition to the effect of the invention according to claim 1, in one process consisting of setting a pipe in one bulge mold, a large height dimension can be continuously formed. Bulge forming can be performed to form the convex portions in three or more locations.

According to the invention according to claim 3, in addition to the effect of the invention according to claim 1, since no device such as an actuator is used in the bulge mold, the structure of the bulge mold can be simplified. can.

According to the invention according to claim 4, in addition to the effect of the invention according to claim 2, since only one bulge mold is required, the required number of bulge molds can be minimized.

According to the invention according to claim 6, in addition to the effect of the invention according to claim 4, since the second piston is provided, the top of the convex portion can be shaped in a shape along the second piston. It has the effect of being moldable.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a first embodiment of the present invention. FIGS. 2 to 4 are explanatory diagrams of the working state of the same embodiment. FIG. 5 is a sectional view of a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a second embodiment of the present invention. 6 to 8 are explanatory diagrams of the working state of the same embodiment. FIG. 9 is a cross-sectional view of a bulge forming die for the first step of a bulge forming apparatus for a plurality of convex portions of a pipe according to a third embodiment of the present invention. FIG. 10 is a sectional view of a bulge forming die for the second step of a bulge forming apparatus for forming a plurality of convex portions of a pipe according to a third embodiment of the present invention. FIG. 11 is a sectional view of a bulge forming die for the third step of a bulge forming apparatus for a plurality of convex portions of a pipe according to a third embodiment of the present invention. FIG. 12 is a partially sectional side view of a pipe having a large number of large convex portions to be bulge-formed in the above embodiment. FIG. 13 is a partially sectional side view of a pipe having a large number of small branch pipes. FIG. 14 is a partially sectional side view of a pipe having two branch pipes with large height dimensions. FIG. 15 is a partially sectional side view of a pipe having a large number of branch pipes with large height dimensions. FIG. 16 is a partially sectional side view of a pipe having a large number of convex portions with large height dimensions. [Description of symbols of main parts] 1...Bulge forming device 2...Upper die 3...Lower die 4...Bulge forming die 5...Pipe hole 7...Recess 21. 9... Vertical cylinder part (first cylinder part) 1
0.11... Vertical piston (first piston) 12.
13...Horizontal cylinder part (second cylinder part 14°15...Horizontal piston (second piston) A, 104
B, 104C...Protrusion...Central band...Second band...Outermost band. Fig. Fig. Fig. Fig. Fig. Fig. 12 Fig. 13

Claims (7)

[Claims] (1) Three or more convex portions are bulge-formed on a pipe at predetermined intervals along the axial direction, and these convex portions are formed into the centralmost band consisting of one or two convex portions. The convex part of the most central belt is divided into one or more bands symmetrically toward both ends of the pipe, with each band consisting of a pair of convex parts located symmetrically on both sides of the most central belt as a unit. A bulge forming method for multiple convex portions of a pipe, in which the convex portions are formed first, and then the convex portions in one band other than the most central zone are formed one by one from the most central zone toward both ends of the pipe. . (2) It is characterized in that it is carried out in one process, which consists of setting the pipe in the pipe hole formed by two molds that make up the bulge mold, and setting the pipe in one bulge mold. A method of bulge forming a plurality of convex portions of a pipe according to claim 1. (3) Three or more convex portions are bulge-formed on the pipe at predetermined intervals along the axial direction, and the centralmost band consisting of one or two of the convex portions is When a band consisting of a pair of protrusions located symmetrically on both sides of the center is divided into one or more bands symmetrically toward both ends of the pipe, the shape corresponding to the protrusion in the most central band a bulge forming mold for the first step consisting of a two-part mold in which a recess is formed and a pipe hole communicating with the recess for setting a pipe; A bulge forming mold for the first step and subsequent steps is made of a two-part mold in which a concave portion having a shape corresponding to the convex portion in the band is formed and a hole for a pipe is formed in communication with the concave portion to set a pipe. A bulge forming device for forming multiple convex portions of a pipe. (4) By introducing a pressure medium into the pipe set in the pipe hole formed by the two halves of the bulge mold, the pipe is spaced at a predetermined interval along its axial direction. In this method, three or more convex portions are bulge-formed using one bulge mold, and among the convex portions, one or more convex portions located symmetrically on both sides centering on the most central band consisting of one or two convex portions. When the pipe is divided into one or more bands symmetrically toward both ends of the pipe, each band consisting of a pair of convex portions is formed as a unit, and a concave portion having a shape corresponding to one or two convex portions of the most central zone is formed in the mold. At the same time, cylinder parts communicating with the pipe holes are provided in the parts corresponding to the convex parts in the bands other than the most central belt, and the cylinder parts are provided with cylinder parts that extend to the position of the outer peripheral surface of the pipe or the convex parts. A piston that retreats to a retracted position corresponding to the top of the part is provided, and when forming the convex part of the most central band, this piston is moved to an advanced position with respect to the part corresponding to the convex part of the band other than the most central band. position,
When the convex part of a band other than the most central band is not formed, the part corresponding to the convex part of that band is located in the forward position, and when forming the convex part of a band other than the most central band and after forming. A bulge forming device for forming a plurality of convex portions of a pipe, characterized in that it is provided with a control means for positioning the pipe in a retracted position. (5) The bulge forming apparatus for a plurality of convex portions of a pipe according to claim 4, wherein the piston has an abutment surface having a shape that matches the outer peripheral surface of the pipe. (6) By introducing a pressure medium into the pipe set in the pipe hole formed by the two-part mold that constitutes the bulge mold, the pipe is spaced at a predetermined interval along its axial direction. In this method, three or more convex portions are bulge-formed using one bulge mold, and among the convex portions, one or more convex portions located symmetrically on both sides centering on the most central band consisting of one or two convex portions. When the pipe is divided into one or more bands symmetrically toward both ends of the pipe, each band consisting of a pair of convex portions is formed as a unit, and a concave portion having a shape corresponding to one or two convex portions of the most central zone is formed in the mold. At the same time, a first cylinder part communicating with the pipe hole is provided in each of the parts corresponding to the convex part in the bands other than the most central band, and a cylinder is placed in the first cylinder part at the position of the outer circumferential surface of the pipe. A first piston is provided which moves forward to a predetermined position or retreats to a predetermined retracted position, and a second cylinder part is provided within the mold and communicates with each of the first cylinder parts, and the second cylinder part communicates with each of the first cylinder parts. Within the department,
It moves parallel to the inside and outside of the first cylinder part with respect to the axis of the pipe, and moves forward to an advanced position corresponding to the top of the convex part of the band other than the most central band of the pipe, or retreats to the outside of the first cylinder part. A second piston is provided, and the first piston is
When forming the convex part of the most central belt, the part corresponding to the convex part of the belt other than the most central belt is placed in the forward position, and when the convex part of the belt other than the most central belt is not formed, that belt The part corresponding to the convex part is located at the forward position, and when the convex part of the band other than the most central belt is formed and after molding, the second piston is located at a predetermined retracted position. 5. The apparatus for forming a bulge of a plurality of convex portions of a pipe according to claim 4, further comprising control means for causing the first piston to move backward when the first piston is moving forward, and for moving the first piston to move forward when the first piston is moving backward. . (7) The apparatus for bulging a plurality of convex portions of a pipe according to claim 6, wherein the second piston has a flat surface on which the tops of the convex portions are formed.