JPH02121721A - Manufacture of bent pipe and its apparatus - Google Patents

Abstract

PURPOSE:To improve the working efficiency for the manufacture of a bent pipe by pressing in a stock between an arcuate bent hole and a mandrel to form a bent pipe, pulling out the mandrel and the bent pipe by a supporting rest, restraining the bent pipe by a locking bar from turning and turning the mandrel. CONSTITUTION:The mandrel 7 is inserted into a fixed die 1 having an arcuate bent hole 4 so that it can go in and out. The stock 5 is pressed in by a push bar 14 between the bent hole 4 of a die 1 and the mandrel 7 to form the bent pipe 5'. After it is formed, a supporting rest 6 is rotated to draw out the mandrel 7 and the bent pipe 5' from the die 1. Under such a state, the locking bar 21 is inserted into a boundary part between the supporting rest 6 and the mandrel 7 to lock the tip of the bent pipe 5' and further the supporting rest 6 is turned to restrain the bent pipe 5' from rotating and the mandrel 7 is turned to separate the bent pipe 4 from the mandrel 7. By this method, the working efficiency for the manufacture of the bent pipe can be improved.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is a method of bending a straight pipe made of a material such as stainless steel by press-fitting it into a fixed mold having a curved hole formed in an arc shape. The present invention relates to a manufacturing method and apparatus for forming a tube.

[Prior Art] As this type of manufacturing method and apparatus, the present inventor previously made an invention as shown in FIG. 6, and published US Pat. No. 475,920
This was patented as No. 6.

Briefly explaining this with reference to the drawings, a fixed mold 61 has a white plate 64 formed in an arc shape from an inlet 62 to an outlet 63, and a support plate 66 that allows access to the white plate in the mold. The attached mandrel 67 is inserted and installed from the exit side of the curved hole, and the material 65 is press-fitted from the entrance side into the curved tubular space formed between the mold and the mandrel using a push rod 69 to form a curved tube. After molding, only the mandrel is extracted from the mold by rotating the support base, and the extrusion rod 68 provided on the support base on the side opposite to the mandrel is removed from the inlet side by rotating the support base. In the method and apparatus for manufacturing a curved tube, in which the molded curved tube is extruded from the mold by the extrusion rod by being press-fitted into the mold, the material is pushed into the curved tube-shaped space from the entrance side by the push rod. In the middle of press-fitting, the press-fitting of the push rod was temporarily interrupted, the mandrel was slightly rotated toward the exit side, and then the material was again press-fitted with the push rod.

[Problems to be Solved by the Invention] However, in the above method and apparatus, as described above,
During the forming of the bent pipe, the press-fitting of the push rod is temporarily interrupted, the mandrel is rotated slightly toward the exit side, and then the material is again press-fitted with the push rod, which complicates the forming process and the equipment. Furthermore, there is a problem in that the formed bent pipe is often entrained in the mandrel.

This invention has been made in view of the above-mentioned problems of the conventional technology, and its purpose is to:
To provide a method and apparatus for manufacturing a bent pipe, which simplifies the manufacturing process by performing the forming process of the bent pipe in one step, and facilitates the removal of the formed bent pipe by extracting the formed bent pipe from the mold together with a mandrel. This is what I am trying to do.

[Means for Solving the Problems] In order to achieve the above object, the method and device for manufacturing a bent pipe according to the present invention includes: a fixed mold having a white part formed in an arc shape from the port to the outlet; A mandrel that can be accessed and removed from the mold and is attached to a support is inserted and installed from the exit side of the mold, and the material is pushed into the curved tubular space formed between the mold and the mandrel from the entrance side. A bent pipe is formed by press-fitting, and after forming, the mandrel is removed from the mold together with the formed bent pipe by rotating the support stand, and with the formed bent pipe pulled out from the mold, the mandrel is removed from the support stand. A locking rod is inserted into the boundary of the mandrel to lock the tip of the bent tube, and the support is rotated to suppress rotation of the bent tube by the locking rod and the mandrel is locked. A method for manufacturing a curved tube in which a molded curved tube is separated from the mandrel by rotation; A bent pipe manufacturing device having a mandrel which can be moved in and out of the mold and which is attached to a support base, and a push rod for press-fitting the material, and a locking rod for inserting a locking rod into the mandrel boundary part of the support base. An apparatus for manufacturing a bent pipe, in which a groove is provided, and the locking rod is moved in and out of the groove, and in the above apparatus, an extrusion rod having the same curvature as the mandrel is provided on the support base on the opposite side of the mandrel. This is a pipe manufacturing device.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

Reference numeral 1 denotes a fixed mold having a blank 4 formed in an arc shape from an inlet 2 to an outlet 3, and the die 2 is rounded toward the outside so that the material 5 can be easily inserted.

Reference numeral 6 designates a support base having a mandrel on one side and an extrusion rod 8 on the other side concentrically, and the mandrel 7 and the extrusion rod 8 and the white 4 are also formed concentrically with the same curvature. It can rotate together with the shaft 9 using the shaft 9 as a fulcrum.

The diameter of the mandrel 7 is slightly smaller than the inner diameter of the material 5,
The diameter of the tip of the extrusion rod 8 is approximately equal to the outer diameter of the material 5.

Further, the diameter of the white material 4 is slightly larger than the outer diameter of the material 5.

A gear 10 (see FIG. 4) is attached to one end of the shaft 9, and a rack 11 that engages the gear 10 is installed at the tip of a piston rod 13 of a cylinder 12.

A piston rod 15 having a push rod 14 screwed onto its tip for press-fitting the material 5 into the curved tubular space formed between the mold l and the mandrel 7 from the artificial body 2 side is actuated by a cylinder 16. The diameter of the tip of this push rod 14 is made approximately equal to the outer diameter of the material 5. Further, near the tip of the piston rod 15 there is a holding member 17 that supports and guides the piston rod, and the push rod 14 and the piston rod 15 are screwed together on the mold 1 side of the holding member 17.

A movable material holding member 18 is provided immediately before the population 2 side of the mold l.
is arranged, and the material holding member 18 is connected to a cylinder 19
The piston rod 20 moves into and out of contact with the population 2 side of the mold 1. Therefore, the material holding member 18 has a population of 2! When it is at the position indicated by the imaginary line away from l,
It is preferable that the material to be processed is supplied to the material holding member within one day.

Furthermore, a hole 22 for inserting the locking rod 21 is provided at the mandrel boundary portion of the support base 6. The locking rod 21 is connected to a piston rod 24 of a cylinder 23.

Therefore, when the locking rod 21 is inserted into the groove 22, the locking rod 21 locks the tip of the formed bent tube 5', and the locking rod 21 suppresses rotation of the formed bent tube. (See Figure 2).

Each cylinder 12.16.19.23 has pressure fluid inlet/outlet pipes 25.26.27.2B, 29.30.31, respectively.
, 32 are connected, and the pipe 25° 26 is connected to the switching valve 33,
Pipes 27 and 28 are switching valves 34, and pipes 29 and 30 are switching valves 35.
, the pipes 31, 32 are connected via a switching valve 36 to a pressure generator, for example an air compressor 37.

The piston rods 13, 20.24 and the push rod 14 are provided with protrusions 38, 39, 40.41, the protrusions 38 are in contact with the sensors 42, 43, 44, and the protrusions 39 are in contact with the sensors 4.
5.46, protrusion 40 is in contact with sensor 47.48 and protrusion 41 is in contact with sensor 49.50.

Then, the signals from each sensor are sent to the controller 51,
The controller 51 controls each cylinder 12°16.19.2.
No. 3 switching valves 33, 34, 35, and 36 are controlled.

When the material holding member 18 is located at the position indicated by the temporary line M4 in FIG. 4, the material 5 is supplied to the material holding member 18. Further, the mandrel 7 is housed in the bent hole 4.

A sensor 42, which will be described later, is connected to the switching valve 33 for the controller 5.
A signal is generated to control the switching valve 35 to position b and the switching valve 35 to position d. As a result, the supply of pressure fluid to the cylinder 12 is stopped, the forward movement of the piston rod 13 is stopped, and the pressure fluid enters the rear chamber of the cylinder 19 from the conduit 30 and enters the cylinder 1.
As the pressure fluid in the front chamber 9 is discharged from the conduit 29, the piston rod 20 moves forward, and the material holding member 18 holding the material 5 moves to a position immediately in front of the entrance 2 side of the mold l. Then, the protrusion 39 of the piston rod 20 contacts the sensor 46.

Here, the sensor 46 issues a signal to the controller 51 to control the switching valve 35 to the e position and the switching valve 34 to the g position. As a result, the supply of pressurized fluid to the cylinder 19 is stopped, the forward movement of the piston rod 20 is stopped, and the pressurized fluid enters the rear chamber of the cylinder 16 from the conduit 28, and the pressurized fluid in the front chamber of the cylinder 16 is discharged from the conduit 27. As a result, the piston rod 15 moves forward, and the tip of the push rod 14 presses the material 5 in the material holding member 18 into the curved tubular space formed between the mold and the mandrel from the entrance 2 side.

As the material 5 is press-fitted into the mold l by the push rod 14, the material 5 is gradually bent, and the contact force between the material 5 and the mandrel 7 increases in proportion to the progress of this bending.

When the material 5 is almost completely press-fitted into the mold 1 and the bending process is completed, the protrusion 41 comes into contact with the sensor 49.

Here, the sensor 49 issues a signal to the controller 51 to control the switching valve 34 to the 1 position.

As a result, the pressure fluid enters the front chamber of the cylinder 16 from the conduit 27, and the pressure fluid in the rear chamber of the cylinder 16 is discharged from the conduit 28, causing the piston port l5 to retreat and move the push rod 14 out of the mold 1. Finally, the protrusion 41 is returned to the distant position.
contacts the sensor 50.

Here, the sensor 50 issues a signal to the controller 51 to control the switching valve 34 to the h position and the switching valve 35 to the f position. As a result, the supply of pressure fluid to the cylinder 16 is stopped, the retraction of the piston rod 15 is stopped, and the pressure fluid enters the front chamber of the cylinder 19 from the conduit 29 and the pressure fluid in the rear chamber of the cylinder 19 is discharged from the conduit 30. As a result, the piston rod 20 retreats and returns the material holding member 18 to its original position. The retraction of the piston rod 20 causes the protrusion 39 to come into contact with the sensor 45.

Here, the sensor 45 issues a signal to the controller 51 to control the switching valve 35 to the C position and the switching valve 33 to the C position. As a result, the supply of pressure fluid to the cylinder 19 is stopped, the retraction of the piston rod 20 is stopped, and the pressure fluid enters the front chamber of the cylinder 12 from the conduit 25 and the pressure fluid in the rear chamber of the cylinder 12 is discharged from the conduit 26. The piston rod 13 is retracted, and the rack 11. The shaft 9 is rotated through the gear lO so that the support base 6 is not rotated in a direction away from the mold l. By this rotation of the support base, the bent tube 5' is pulled out of the mold 1 together with the mandrel 7. This retraction of the piston rod 13 causes the third protrusion to come into contact with the sensor 43. At this point, the formed bent pipe 5'
The mandrel 7 is in a state where it has escaped from the mold l (the state shown in FIG. 2).

Here, the sensor 43 issues a signal to the controller 51 to control the switching valve 27 to the b position and the switching valve 36 to the J position. As a result, the pressure fluid enters the rear chamber of the cylinder 23 from the conduit 32 and the pressure fluid in the front chamber of the cylinder 23 is discharged from the conduit 31, so that the piston rod 24 moves forward and the rotation of the support table is temporarily stopped. As the piston rod 24 moves forward, the locking rod 21 enters the locking rod insertion groove 22 formed in the support base 6 and locks the tip of the formed bent pipe 5'' (as shown by the imaginary line in FIG. 2). In this locked state, the protrusion 40 contacts the sensor 47.

At this time, the sensor 47 issues a signal to the controller 51 to control the switching valve 36 to the position C and the switching valve 33 to the C position. As a result, the pressure fluid enters the front chamber of the cylinder 12 again from the conduit 25, and the pressure fluid in the rear chamber of the cylinder 12 is discharged from the conduit 26, so that the piston rod 13
further retreats and rack 11. The shaft 9 is rotated via the gear 10 so as not to rotate the support base 6 further away from the mold l. When the support base is rotated, the mandrel 7 is moved to the support base 6.
However, the tip of the formed bent pipe 5' is connected to the locking rod 2.
1, rotation is suppressed. Therefore, the forming bent tube is removed from the mandrel 7 as the support base is rotated. The protrusion 38 contacts the sensor 44 when the forming bent tube 5' is completely removed from the mandrel 7 (the state shown in FIG. 3).

Here, the sensor 44 issues a signal to the controller 51 to control the switching valve 36 to the m position and the switching valve 33 to the a position. As a result, the pressure fluid enters the front chamber of the cylinder 23 from the conduit 31 and the pressure fluid in the rear chamber of the cylinder 23 is discharged from the conduit 32, causing the piston rod 24 to retreat, and the pressure fluid flows from the conduit 26 to the cylinder 12. The pressure fluid in the front chamber of the cylinder 12 enters the rear chamber and is discharged from the conduit 25, thereby causing the piston rod 13 to move forward. Therefore, as the locking rod 21 moves back, the piston rod 13
Rack 11. The shaft 9 connects to the support base 6 via the gear 10.
The mold is rotated without being rotated in one direction. By this rotation of the support base, the mandrel 7 is sequentially inserted into the curved hole 4 of the mold 1. When the mandrel 7 is fully inserted into the artist 4, the protrusion 38 contacts the sensor 42.

Here, the sensor 42 issues a signal to the controller 51 to control the switching valve 33 to the b position and the switching valve 35 to the d position. As a result, the supply of pressure fluid to the cylinder 12 is stopped, the piston rod 13 stops moving forward, and the pressure fluid enters the rear chamber of the cylinder 19 from the conduit 30 and enters the cylinder 19.
The pressurized fluid in the front chamber is discharged from the conduit 29, causing the piston rod 20 to move forward and direct the material holding member 18 toward the mold l.

By repeating this process, the bending process is performed automatically and sequentially, and the material 5 is supplied to the material holding member 18 when the material holding member 18 is at the position indicated by the imaginary line in FIG. 4 away from the mold. It is something to do.

Incidentally, although the bent pipe is formed in the above order, when the mandrel 7 is extracted from the blank 4 of the mold l, the formed bent pipe 5' may sometimes be left behind in the blank 4. In this case, the extrusion rod 8 rotating together with the support base 6 is
By pressing the rear end of the molded bent pipe 5', the molded bent tube 5' is pulled out from the blank 4 of the mold 1.

In addition, when the diameter of the material 5 changes, a mandrel 7 corresponding to its inner diameter and an extrusion rod 8 corresponding to its outer diameter are attached to the support stand 6, and a mold having a blank 4 corresponding to its outer diameter is attached. 1, the push rod 14 corresponding to its outer diameter is screwed onto the piston rod 15, and the material holding member 18 corresponding to the outer diameter is attached to the piston rod 20.

Further, examples of the pressure fluid include pressure oil, compressed air, etc., and possible sources thereof include a pump, an air compressor, etc.

Furthermore, in this embodiment, a horizontal type device has been described, but the device is not limited to a horizontal type, but may be a vertical type.

[Effects of the Invention] According to the present invention, the process of forming a curved pipe can be carried out in one process, so that the manufacturing process is simplified and the apparatus is also simplified accordingly. Furthermore, by removing the molded bent tube from the mold together with the mandrel, the molded bent tube can be taken out extremely easily. Furthermore, even if the molded bent tube remains in the mold, it can be taken out from the mold extremely easily by the extrusion rod. The production of bent pipes can be easily automated using a control device using a simple sensor controller, making it possible to significantly improve work efficiency.

Furthermore, by arranging a movable material holding member on the entrance side of the mold, it is not only easier to supply the material, but also the material can be reliably press-fitted into the mold by the push rod. Become.

[Brief explanation of drawings]

Fig. 1 is a side cross-sectional view of an apparatus suitable for carrying out the method for manufacturing a bent pipe according to the present invention, Fig. 2 is a diagram showing a state in which a formed bent pipe is pulled out from a mold, and Fig. 3 is a diagram showing a formed bent pipe placed on a mandrel. 4 is a plan view of the device shown in FIG. 1, FIG. 5 is a control circuit diagram, and FIG. 6 is a side sectional view of a conventional bent pipe manufacturing device. 1... Fixed mold, 2... Curved hole entrance, 3... Curved hole exit, 4... White person, 5... Material, 5'... Molded bent pipe, 6... Support Stand, 7... Mandrel, 8... Extrusion rod, 9... Shaft, 12.16, 19.23... Cylinder, 13.15.20.24... Piston rod, 14
... Push rod, 18... Material holding member, 21... Locking rod, 22... Locking rod insertion groove, 42-50... Sensor, 51... Controller.

Claims (1)

[Scope of Claims] [1] In a fixed mold having a curved hole formed in an arc shape from an inlet to an outlet, a mandrel that can move in and out of the curved hole in the mold and is attached to a support is bent. The material is inserted from the outlet side of the hole, and the material is press-fitted from the entrance side into the curved tube-shaped space formed between the mold and the mandrel using a push rod to form a curved tube. After forming, the support base is rotated. The mandrel is removed from the mold together with the bent tube by moving the bent tube, and with the bent tube removed from the mold, a locking rod is inserted into the boundary between the support and the mandrel to remove the bent tube. The tip of the molded bent pipe is locked, and the support base is further rotated to suppress the rotation of the molded bent pipe by the locking rod, and the mandrel is rotated to separate the molded bent pipe from the mandrel. A method for manufacturing bent pipes. [2] A fixed mold having a curved hole formed in an arc shape from the entrance to the exit, a mandrel that can move in and out of the curved hole in the mold and is attached to a support base, and a push rod for press-fitting the material. 1. An apparatus for manufacturing a bent pipe, characterized in that a groove for inserting a locking rod is provided at a mandrel boundary portion of the support base, and the locking rod is moved into and out of the groove. [3] Claim 2, wherein the support base is provided with an extrusion rod having the same curvature as the mandrel on the opposite side of the mandrel.
The bent pipe manufacturing device described above.