JPH02290622A - Apparatus for bending pipe - Google Patents

Abstract

PURPOSE:To bend pipe without reducing the thickness of a pipe whether the pipe length is long or short and whether the pipe diameter is large or small by cramping the pipe with a forcing die and a clamping member arranged at the neighbor of the bending die and applying the compressing force to the axial direction. CONSTITUTION:The pipe clamping member 14 is arranged at the neighbor of the bending die 1 and the pipe P is clamped between the above and the forcing die 6 and the compressing force is applied to the axial direction of the pipe. A space is kept to be able to move the clamping member 14 and the forcing die 6 in accordance with the bending shape of the pipe P and the compressing force in the axial direction is applied while holding the middle of the pipe P without pushing the end of the pipe. In such a way, whether the length and the diameter of the pipe are large or small, the bending work is executed without buckling and thickness reducing and the apparatus is able to be miniaturized.

Description

[Detailed Description of the Invention] Industrial Application Fields of the Invention (Table) Regarding a pipe bending device for bending a pipe, Feature 1: Pipe bending that suppresses wall thinning when bending a pipe with a small radius Regarding processing equipment.

[Prior Art] Conventionally, in order to suppress the local thinning of the pipe wall that occurs during bending of the pipe, it has been known to apply compressive force in the axial direction of the pipe during bending. There is. analogy fi
As disclosed in Japanese Patent Application Laid-Open No. 58-205620, a bending process in which a means for applying an axial compressive force corresponding to the rotation angle of a bending die to the pipe is added, and the pipe is bent while applying the axial compressive force by the applying means. The device is known. Also,
As disclosed in Japanese Patent Application Laid-Open No. 61-222634, a stretching device that fixes one end of a pipe and performs a stretching bending process, a compression bending device that applies a compressive load to the other end of the pipe and performs a compression bending process, There are also known devices that include a side bending device that performs side bending by press-contacting the side surface of a pipe, and perform these three bending processes at the same time.

[Problems to be Solved by the Invention] However, with these conventional bending devices, the end of the pipe is pushed by a hydraulic cylinder during bending.
In addition, by pressing the pressure mold against the pipe and using the friction force,
A compressive load was applied in the axial direction of the pipe.When pushing with a hydraulic cylinder, it works well when the pipe is short, but when the pipe has a small diameter and is long, the end of the long small diameter pipe is pressed with a hydraulic cylinder. When pressure is applied, the pipe may buckle. However, there are cases where sufficient axial compressive force cannot be applied only by the friction force between the pressure die and the pipe, and thinning during bending cannot be reliably suppressed. Therefore, the present invention aims to solve the above-mentioned problems and provides a pipe bending device that reliably suppresses wall thinning during pipe bending.

[A thousand steps to solve the problem] In order to achieve the above object, the present invention has the following configuration as a means for solving the problem. Namely, a bending die that can rotate a long pipe, A pressure die is placed around the bending die and clamped by a rotatable clamping die, and is placed in contact with the pipe to receive a bending reaction force, and the clamping die is rotated as the bending die rotates to bend the pipe. The pipe bending apparatus includes a clamping member that moves opposite to the pressure die and clamps the pipe together with the pressure die, and the pressure die and the clamping die are aligned with the axis of the pipe as the pipe is bent. This is the structure of a pipe bending device characterized by being equipped with a moving mechanism that moves in the direction and applies compressive force in the axial direction.

[Function] The pipe bending apparatus having the above structure holds a long pipe between the bending die and the clamping die, and brings the pressure die into contact with the pipe.1:. The pressure mold and the clamping member clamp the pipe. As the pipe is bent, the moving mechanism moves the pressure mold and the clamping member in the axial direction of the pipe to apply an axial compressive force. Therefore, thinning can be reliably suppressed during bending of the pipe.

[Example] Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a schematic layout diagram of a pipe bending apparatus which is an embodiment of the present invention. The pipe bending apparatus of this embodiment is for bending a pipe P, and 1 is a bending die, in which a groove 2 is formed in accordance with the bending shape. A clamping die 4 is disposed facing the bending die 1 and moving in the eight directions of arrows in the figure to clamp the pipe P together with the bending die 1.

Furthermore, the bending die 1 (which is rotatable by a drive mechanism not shown in the table, and the clamping die 4 is also made to revolve around the bending die 1 while holding the pipe P between the bending die 1 and the bending die 1). There is.

Furthermore, the pressure die 6 which is in contact with the pipe P and is capable of receiving a bending reaction force during bending is a bending die.
It is arranged along the axial direction of the pipe P near the pipe P. In this embodiment, as shown by the arrow B in the figure, the pressure mold 61 is placed on a movable table 10, driven by a hydraulic cylinder 8, and guided so as to be movable in the radial direction of the pipe P. This makes it easy to attach the pipe P to the bending die 1.A wiper 12 is provided opposite the pressure die 6 and close to the bending die 1 on the opposite side of the pipe P. This wiper 12 is designed to suppress the generation of wrinkles on the inside of the pipe P during bending.

Also, on the opposite side of the pipe P, facing the pressure mold 6, a holding member 14 is placed on a movable table 10 and guided so as to be movable in the radial direction of the pipe P, as shown by arrow C in the figure. ing. Then, the clamping member 14 (the hydraulic cylinder 16
It is made to move by being driven by. The moving table 1019 is supported so as to be movable along the axial direction of the pipe P toward the bending die 1, as shown by arrow D in the figure, and the moving table 10 is driven by a hydraulic cylinder 18 to move. being done. This hydraulic cylinder 18 (
Hydraulic oil is supplied via the upper hydraulic servo mechanism 20.

On the other hand, the other end of the pipe P is configured to be held by a chuck 26 mounted on a carriage 24 that is self-propelled along a rail 22 installed in the axial direction of the pipe P. An encoder 28 is provided that outputs a pulse signal according to the rotation angle of the mold, and the hydraulic servomechanism 20 is controlled in accordance with this pulse signal to control the moving speed of the movable table 10 by driving the hydraulic cylinder 18. A control device 30 is provided.

Next, the operation of the pipe bending apparatus of this embodiment will be explained.

First, one end of the pipe P is attached to the groove 2 of the bending die 1. The other end of the pipe P is held by the chuck 26 of the carriage 24 located at the rear. Next, the carriage 24 is moved along the rail 22 by a predetermined amount in the direction of arrow E in the figure, that is, in the axial direction of the pipe P, to the first bending position. Then, the clamping die 4 is moved in the eight directions of the arrows in the figure, and the pipe P is held between the bending die 1 and the clamping die 4. Subsequently, hydraulic oil is supplied to the hydraulic cylinder 8, and the pressure mold 6 is moved toward the pipe P so as to come into contact with the pipe P. Next 1: Hydraulic oil is supplied to the hydraulic cylinder 16, the clamping member 14 is moved toward the pipe P,
The pipe P is held between the holding member] 4 and the pressure mold 14.

When the pipe P is held between the clamping member [4] and the pressure die [4], the bending die] and the clamping die [4] are both rotationally driven in the direction of the arrow ``in the figure, and the pipe P is bent. This bending reaction force is received by the pressure mold 6.

Further, along with this rotational drive, the rotation of the bending mold is detected by the encoder 28. The hydraulic servo mechanism 20 is controlled by the control device 3o in response to the pulse signal output from the encoder 28, and the hydraulic servo mechanism 20 is actuated to the hydraulic cylinder 18. Oil is supplied. The amount of hydraulic oil supplied to this hydraulic cylinder 18 (
It depends on the rotation angle and rotation speed of the bending mold 1 calculated based on the pulse signal, and the axial compressive force is applied to the pipe P by moving the movable table 1o according to the amount of hydraulic oil supplied to the hydraulic cylinder 18. It is designed to be added. example{
According to the calculated rotational speed of the bending die 1, the control amount of the hydraulic servo mechanism 20 is read from a map etc. stored in the control head 30 in advance. By controlling the hydraulic servo mechanism 20 according to this control amount and supplying a predetermined amount of hydraulic oil to the hydraulic cylinder 18,
The pressure die 6 and the clamping member 14 move to follow the pipe P that moves with the rotation of the bending die 1, and the pressure die 6 and the clamping member 14 move the pipe P clamped by the pressure die 6 and the clamping member 14 in a predetermined axial direction. A compressive force is applied.

In addition, when the rotation angle of the bending mold is small, for example, the rotation angle is 60 degrees or less, the bending process can be performed by controlling the axial compressive force to gradually increase until the rotation angle reaches 60 degrees. Initial buckling can be prevented.

In this way, the pipe P is held between the holding member 14 and the pressure mold 6, hydraulic oil is supplied to the hydraulic cylinder 18, and the holding member 14 and the pressure mold 6 are connected to the pipe P via the moving table 10.
move in the axial direction. Due to this, an axial compressive force is generated in the pipe P which is held between the holding member 14 and the pressure mold 6. In this way, a compressive force is applied to the pipe P in the axial direction during the bending process of the pipe P, and thinning due to plastic deformation on the back side of the pipe P during the bending process can be suppressed.

When the bending process is completed, the clamping of the pipe P between the bending die and the clamping die 4 and the clamping of the pipe P between the clamping member 14 and the pressure die 6 are released. Next, the carriage 24 is moved a predetermined l in the axial direction of the pipe P to move the pipe P to the next bending position. And, as mentioned above,
The clamping die 4, the pressure die 6, and the clamping member 14 are moved, and during the bending process using the bending die 1 and the clamping die 4, the pipe P is clamped by the pressure die 6 and the clamping member]4, and the shaft is attached to the pipe P. Add directional compressive force. Such operations are repeated to bend one pipe P at a plurality of locations, and when the bending process is completed, the chuck 26 is released and the pipe P is removed from the carriage 24.

As described above, according to the pipe bending apparatus 2 of this embodiment, when the pipe P is bent by the bending die 1 and the clamping die 4, the pipe P is held by the clamping member 14 and the pressure die 6, and the bending process is performed by During processing, the clamping member 14 and the pressure die 6 are moved in the axial direction via the moving table 10 by the hydraulic cylinder 18 to apply an axial compressive force.

Therefore, since the pipe P is clamped by the clamping member 14 and the pressure mold 6 provided near the bending mold 1 and compressive force in the axial direction is applied, it is possible to apply a compressive force in the axial direction. Regardless of the size of the diameter of the pipe P, axial compressive force can be reliably applied without causing buckling. Furthermore, it is only necessary to secure a space in which the clamping member 14 and the pressure die 6 can be moved according to the bent shape of the pipe P, and in addition, instead of pushing the end of the pipe P, the shaft is held by clamping the middle of the pipe P. Since directional compressive force is applied, it can be applied regardless of the length of the pipe P. Furthermore, just because the pipe P is long, there is no need to increase the size of the entire device.

The present invention is not limited to these embodiments in any way, and may be implemented in various forms without departing from the gist of the present invention.

[Effects of the Invention] As detailed above, the pipe bending device of the present invention can reliably apply axial compressive force regardless of the length of the pipe or the diameter of the pipe. It is only necessary to secure a space in which the holding member and the pressure mold can be moved according to the bending shape of the device h{.

[Brief explanation of the drawing]

FIG. 1 is a schematic layout of a pipe bending apparatus as an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line a-a in FIG. 1. P... Pipe 1... Bending die 4... Clamping die 6... Pressure die 8, 16.18... Hydraulic cylinder 10... Moving table 14... Holding member agent
Patent attorney Tsutomu Adachi ←i-4ki Figure 1 Figure 2

Claims (1)

[Scope of Claims] A long pipe is held between a rotatable bending mold and a clamping mold that can revolve around the bending mold, and a pressure mold is disposed in contact with the pipe and receives a bending reaction force. The pipe bending apparatus bends the pipe by rotating the clamping die together with the rotation of the bending die, further comprising a clamping member that moves opposite to the pressure die and clamps the pipe together with the pressure die, A pipe bending apparatus comprising a moving mechanism that moves the pressure mold and the clamping mold in the axial direction of the pipe to apply an axial compressive force as the pipe is bent.