JP4539932B2

JP4539932B2 - Bending method for thin metal pipe

Info

Publication number: JP4539932B2
Application number: JP2000009057A
Authority: JP
Inventors: 正樹星野
Original assignee: Usui Co Ltd
Current assignee: Usui Co Ltd
Priority date: 2000-01-18
Filing date: 2000-01-18
Publication date: 2010-09-08
Anticipated expiration: 2020-01-18
Also published as: JP2001205349A

Description

【０００１】
【発明の属する技術分野】
本発明は細径金属管の曲げ加工技術に関するものである。
【０００２】
【従来の技術】
従来細径金属管の曲げ加工は、主として手動操作される治具を用いて手動加工により行なわれていた。しかし細径金属管の曲げ加工を手動で行なうと、充分な加工精度が得られず、加工能率も悪い。一方で特定形状の曲げ加工を自動的に行なうパワーベンダーと呼ばれる曲げ加工装置や、各種の曲げ加工を自動的に行なうＮＣベンダーと呼ばれる曲げ加工装置も使用されている。パワーベンダーは設備コストが比較的安く、且つ加工精度と加工能率上の問題を解決するが、特定形状の曲げ加工しかできず、形状変更に対応しにくいという難点がある。またパワーベンダーは、細径金属管に複雑な加工を短時間で施すことができるが、構造が複雑で設備費上でも問題があり、保守も煩雜である。また、加工条件を変化させるためのセットも複雑で時間がかかる。
【０００３】
一方、ＮＣベンダーは被加工細径金属管の軸芯方向に設定した複数箇所の被加工位置に対して、それぞれ設定された加工方向にそれぞれ設定された曲げ加工を施す装置であり、具体的には被加工細径金属管の一端側をチャックし、前記被加工細径金属管を軸芯を中心に回転して所定の加工方向を設定し、かつ前記被加工細径金属管を軸芯方向に移動して所定の被加工位置に設定するパイプひねりユニットと、前記被加工細径金属管を挟持して所定角度回動し、前記被加工細径金属管に引張りながら曲げ加工を施す曲げ加工手段を備えた構成となったもので、被加工細径金属管の一端側を把持するチャック装置、このチャック装置にてチャックされた被加工細径金属管を軸芯を中心に回転して所定の加工方向を設定し、かつ前記被加工細径金属管を軸芯方向に移動して所定の被加工位置に設定するパイプひねりユニットと、曲げロールおよびこの曲げロールの周面に被加工細径金属管を押圧しながら、この被加工細径金属管を介して前記周面上を所定角度回動し、前記被加工細径金属管の他端の先端側よりチャックされた一端に向けて順次引張り曲げ加工するクランプ治具と、曲げ加工時における被加工細径金属管の反力受を有する曲げ装置を備えている。
【０００４】
図２はパイプを引張りながら曲げ加工を施すＮＣベンダーによる曲げ加工方法を例示したもので、曲げ装置１１は、曲げロール１１−１とこの曲げロールの周面に前記被加工細径金属管Ｐを押圧しながら、この被加工細径金属管を介して前記周面上を所定角度回動し曲げ加工する狭幅のクランプ治具１１−２と、プレッシャーダイ（反力受）１１−４を備え、曲げロール１１−１とクランプ治具１１−２はベンドアーム１１−３に一体に取付けられている。
【０００５】
すなわち従来の曲げ加工は、被加工細径金属管Ｐを曲げロール１１−１とクランプ治具１１−２にてクランプした後、プレッシャーダイ（反力受）１１−４を前進移動させて被加工細径金属管Ｐに当接させ、この状態でベンドアーム１１−３を所定角度回動して曲げ加工を施している。この曲げ加工時、被加工細径金属管Ｐはクランプ治具１１−２にて引張られながら曲げロール１１−１の周面に押圧されながら曲げ加工が施される。
【０００６】
【発明が解決しようとする課題】
しかるに、前記した従来の曲げ加工方法では、被加工細径金属管Ｐを曲げロール１１−１とクランプ治具１１−２にてクランプした状態で引張りながら一動作で所定の曲げ加工を施すため、被加工細径金属管Ｐを強くクランプしなければならず、その曲げ加工の際には図３に示すごとく被加工細径金属管Ｐに矢印のような大きなクランプ力がかかるため、被加工細径金属管Ｐの表面に局部的な座屈が発生しクランプ痕と称する凹状の食込み疵が付くという問題がある。また、同図に示すごとく、前工程の曲げ止まり位置と次工程の曲げ始め位置が近い場合には被加工細径金属管Ｐの直線部分がほとんどない状態となるので、これに対応するためには図４に示すごとく曲げロール２１−１とクランプ治具２１−２に前工程の曲げ形状に合せた溝２１−３を作成した総型２１とする必要があり、型コストが高くつくのみならず、この曲げ専用型のみでは直線状の曲げに対応できないため、図４に示すごとく直線状の溝２１−３′を形成した曲げロール２１−１′とクランプ治具２１−２′を設けた二段式の曲げユニットとする必要があるなどの難点があった。
【０００７】
本発明はかかる問題を解決するためになされたもので、従来と同様のＮＣベンダーにより被加工細径金属管の表面に凹状のクランプ痕が生じないように曲げ加工することが可能で、かつ総型や二段式曲げユニットなども不要な細径金属管の曲げ加工方法を提案しようとするものである。
【０００８】
【課題を解決するための手段】
前記課題を解決するために、本発明に係る細径金属管の曲げ加工方法は、曲げロールとクランプ治具を途中の曲げ位置まで回動させた状態でプレッシャーダイ（反力受）にて被加工細径金属管を押し曲げる方法と、この押し曲げた後引き続いて引張り曲げ加工を施す方法であり、その第１の実施態様は被加工細径金属管をその軸芯を中心に所定角度回動して加工方向を設定し、この被加工細径金属管を曲げロールとパイプクランプ治具とで挾持し、かつ反力受を加工位置へ移動させて被加工細径金属管に当接させた状態で、前記曲げロールの周面に前記被加工細径金属管を押圧しながら該曲げロールと前記クランプ治具を所定角度回動させて前記被加工細径金属管を引張りながら曲げ加工を施す曲げ加工方法において、前記被加工細径金属管を引張りながら曲げ加工を施す前に、被加工細径金属管を曲げロールとパイプクランプ治具とで挾持した後、パイプ後端を開放させ、反力受を加工位置へ移動させる前に前記曲げロールとパイプクランプ治具を曲げ角度回動させて被加工細径金属管を反力受側に回動位置させ、次いで反力受を加工位置へ移動させて被加工細径金属管を前記曲げ角度押し曲げることを特徴とし、
また第２の実施態様は前記の押し曲げ加工に引き続いて、前記クランプ治具を所定角度回動させて前記被加工細径金属管に引張りながら曲げ加工を施すことを特徴とするものである。
【０００９】
【発明の実施の形態】
図１は本発明に係る細径金属管の曲げ加工方法の一実施例を示す概略斜視図である。
【００１０】
すなわち本発明に係る細径金属管の曲げ加工は、図１に示すように曲げ装置１により被加工細径金属管Ｐを曲げ加工するに際し、被加工細径金属管Ｐを曲げロール１−１とクランプ治具１−２にてクランプした後パイプ後端を開放し、プレッシャーダイ（反力受）１−４は被加工細径金属管Ｐより離れた位置で、ベンドアーム１−３を途中の曲げ位置まで角度θ回動させて被加工細径金属管Ｐの未加工側をプレッシャーダイ（反力受）１−４側に位置させ、この状態でプレッシャーダイ（反力受）１−４を加工位置まで前進移動させて曲げロール１−１の円弧溝に前記被加工細径金属管Ｐを押圧しながら曲げ角度θの第１段の曲げ加工を施す。この第１段の曲げ加工は、プレッシャーダイ（反力受）１−４による押し曲げであるから、被加工細径金属管Ｐにかかるクランプ力は比較的小さくて済み、チャックの前工程側角部に大きな力が集中することがない。したがって、この曲げ加工の際には被加工細径金属管Ｐの表面に座屈による凹状のクランプ痕と称する食込み疵などが付くことはほとんどない。
【００１１】
前記第１段の押し曲げ加工が終了すると、第２段（最終曲げ）の曲げ加工を施すため、プレッシャーダイ（反力受）１−４をその第１段の曲げ位置に固定した状態でベンドアーム１−３を残りの角度回動して最終の曲げ加工を施す。この曲げ加工は被加工細径金属管Ｐがクランプ治具１−２にて引張られながら曲げロール１−１の円弧溝に押圧されながら曲げ加工が施される。この時被加工細径金属管Ｐは第１段の押し曲げ加工により一部曲げられているため、残りの曲げを引張り曲げ加工により行っても、被加工細径金属管Ｐは曲げロール１−１の円弧溝にはまり込んだ状態で摩擦力を受けるため被加工細径金属管Ｐを強くクランプする必要はない。したがってこの第２段の引張り曲げ加工の際にも被加工細径金属管Ｐに大きなクランプ力がかかることがないため、被加工細径金属管Ｐの表面にクランプ痕と称する食込み疵などが付くことはほとんどない。なお曲げ角度が小さい場合にはその後の曲げはなくてもよい。
【００１２】
【発明の効果】
以上説明したごとく、本発明は曲げロールとクランプ治具を途中の曲げ位置まで回動させた状態でプレッシャーダイ（反力受）にて細径金属管を押し曲げる方法であり、またその押し曲げに引き続いて引張り曲げにより曲げ加工を施す方法であるから、押し曲げ加工時および引張り曲げ加工時に細径金属管に大きなクランプ力がかかることがなく、よって表面に凹状のクランプ痕と称する食込み疵などがほとんどない高品質の曲げ加工製品を得ることができるという優れた効果を奏する。さらに、本発明は総型や二段式曲げユニットなども不要であるため設備費が高くつくこともない。
【図面の簡単な説明】
【図１】本発明に係る細径金属管の曲げ加工方法の一実施例を示す概略斜視図である。
【図２】本発明の対象とする従来の細径金属管の曲げ加工方法の一例を示す概略斜視図である。
【図３】図２に示す従来の曲げ加工方法の要部を拡大して示す概略斜視図である。
【図４】同じく従来の細径金属管の曲げ加工方法の他の例を示す概略斜視図である。
【符号の説明】
１曲げ装置
１−１曲げロール
１−２クランプ治具
１−３ベンドアーム
１−４プレッシャーダイ（反力受）
Ｐ被加工細径金属管[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bending technique for a thin metal tube.
[0002]
[Prior art]
Conventionally, bending of a thin metal tube has been performed by manual processing mainly using a manually operated jig. However, if the thin metal pipe is manually bent, sufficient processing accuracy cannot be obtained and the processing efficiency is poor. On the other hand, a bending apparatus called a power bender that automatically performs bending of a specific shape and a bending apparatus called an NC bender that automatically performs various bending processes are also used. Power vendors have relatively low equipment costs and solve the problems of machining accuracy and machining efficiency. However, power vendors can only bend specific shapes and have difficulty in adapting to shape changes. In addition, power vendors can perform complicated processing on small-diameter metal tubes in a short time, but the structure is complicated, there is a problem in terms of equipment costs, and maintenance is troublesome. Moreover, the set for changing the processing conditions is complicated and takes time.
[0003]
On the other hand, the NC bender is a device that performs bending processing set in each set processing direction on a plurality of processing positions set in the axial direction of the thin metal pipe to be processed. Chucks one end of the small metal pipe to be processed, sets the predetermined processing direction by rotating the thin metal pipe to be processed around the axial center, and sets the small metal pipe to the axial direction. A pipe twisting unit that moves to a predetermined processing position and a bending process in which the processing small diameter metal tube is sandwiched and rotated by a predetermined angle and bent while being pulled to the processing small diameter metal tube A chuck device that grips one end of a thin metal pipe to be processed, and a predetermined thin metal pipe that is chucked by the chuck device around an axis. The processing direction of the metal and the thin metal to be processed A pipe twist unit that moves the shaft in the axial direction and sets it at a predetermined processing position, and the bending roll and the small metal pipe to be processed while pressing the thin metal pipe on the peripheral surface of the bending roll. A clamping jig that rotates by a predetermined angle on the peripheral surface and sequentially pulls and bending toward one end chucked from the tip end of the other end of the thin metal pipe to be processed, and a workpiece to be processed at the time of bending A bending apparatus having a reaction force receiver for a thin metal pipe is provided.
[0004]
FIG. 2 exemplifies a bending method by an NC bender that performs bending while pulling a pipe. A bending device 11 includes a bending roll 11-1 and the thin metal pipe P to be processed on the peripheral surface of the bending roll. A narrow clamping jig 11-2 that rotates and bends on the peripheral surface by a predetermined angle through the thin metal pipe to be processed while pressing and a pressure die (reaction force receiver) 11-4 are provided. The bending roll 11-1 and the clamp jig 11-2 are integrally attached to the bend arm 11-3.
[0005]
In other words, in the conventional bending process, a small metal pipe P to be processed is clamped by a bending roll 11-1 and a clamp jig 11-2, and then a pressure die (reaction force receiver) 11-4 is moved forward to be processed. The bend arm 11-3 is rotated by a predetermined angle in this state to be brought into contact with the small-diameter metal tube P, and bending is performed. During this bending process, the thin metal pipe P to be processed is bent while being pressed by the clamp jig 11-2 against the peripheral surface of the bending roll 11-1.
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional bending method, in order to perform a predetermined bending process in one operation while pulling in a state where the thin metal pipe P to be processed is clamped by the bending roll 11-1 and the clamping jig 11-2, The thin metal pipe P to be processed must be strongly clamped, and a large clamping force such as an arrow is applied to the thin metal pipe P to be processed as shown in FIG. There is a problem that local buckling occurs on the surface of the diameter metal pipe P and a concave bite called a clamp mark is attached. Also, as shown in the figure, when the bending stop position of the previous process and the bending start position of the next process are close, there is almost no straight portion of the thin metal pipe P to be processed. As shown in FIG. 4, it is necessary to make the total mold 21 in which the groove 21-3 matched to the bending shape of the previous process is formed on the bending roll 21-1 and the clamping jig 21-2, and the mold cost is high. Since only this bending type cannot cope with linear bending, a bending roll 21-1 'and a clamping jig 21-2' having a linear groove 21-3 'are provided as shown in FIG. There were difficulties such as the need for a two-stage bending unit.
[0007]
The present invention has been made to solve such a problem, and can be bent by an NC bender similar to the conventional one so that a concave clamp mark is not formed on the surface of the thin metal pipe to be processed. The aim is to propose a bending method for thin metal pipes that does not require a mold or a two-stage bending unit.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problems, a bending method of a thin metal pipe according to the present invention is performed by a pressure die (reaction force receiver) in a state where a bending roll and a clamp jig are rotated to a middle bending position. A method of pushing and bending a machined thin metal tube, and a method of subsequently subjecting the machined thin metal tube to tensile bending, and the first embodiment is a method of rotating the machined thin metal tube a predetermined angle around its axis. The processing direction is set by moving the small metal pipe to be processed with a bending roll and a pipe clamp jig, and the reaction force receiver is moved to the processing position to contact the thin metal pipe to be processed. In this state, the bending roll and the clamp jig are rotated by a predetermined angle while pressing the thin metal pipe to be processed against the peripheral surface of the bending roll, and bending is performed while pulling the thin metal pipe to be processed. in bending method performed, the processed thin metal tube Before performing the bending while pulling, after sandwiched by the roll and the pipe clamp jig to bend the workpiece small diameter metal tube, the bending roll before opens the pipe rear end, to move the reaction force receiving the machining position The pipe clamp jig is rotated at the bending angle to move the thin metal pipe to be processed to the reaction force receiving side, and then the reaction force receiver is moved to the processing position so that the thin metal pipe to be processed is at the bending angle. Characterized by pushing and bending,
In addition, the second embodiment is characterized in that, following the push bending process, the clamping jig is rotated by a predetermined angle and bent while being pulled on the thin metal pipe to be processed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic perspective view showing an embodiment of a bending method of a thin metal pipe according to the present invention.
[0010]
That is, the bending of the thin metal tube P according to the present invention is performed when the thin metal tube P to be processed is bent by the bending apparatus 1 as shown in FIG. After clamping with the clamping jig 1-2, the rear end of the pipe is opened, and the pressure die (reaction force receiving) 1-4 is separated from the thin metal pipe P to be processed, and the bend arm 1-3 is in the middle. Is rotated to the bending position of [theta] and the unprocessed side of the thin metal pipe P to be processed is positioned on the pressure die (reaction force receiving) 1-4 side, and in this state, the pressure die (reaction force receiving) 1-4 is placed. Is moved forward to the processing position, and the first-stage bending process of the bending angle θ is performed while pressing the thin metal pipe P to be processed into the arc groove of the bending roll 1-1. Since the first stage bending process is a push bending process using a pressure die (reaction force receiver) 1-4, the clamping force applied to the thin metal pipe P to be processed can be relatively small. There is no big power concentrated on the club. Therefore, during this bending process, the surface of the thin metal pipe P to be processed is hardly attached with a bite or the like called a concave clamp mark due to buckling.
[0011]
When the first stage push bending process is completed, the second stage (final bending) bending process is performed, and the pressure die (reaction force receiver) 1-4 is bent in the first stage bending position. The arm 1-3 is rotated by the remaining angle to perform the final bending process. In this bending process, the thin metal pipe P to be processed is bent by being pressed by the arc groove of the bending roll 1-1 while being pulled by the clamp jig 1-2. At this time, since the thin metal pipe P to be processed is partially bent by the first-stage push bending process, even if the remaining bending is performed by the tensile bending process, the thin metal pipe P to be processed is the bending roll 1- Since the frictional force is received in a state of being fitted in the arcuate groove 1, it is not necessary to strongly clamp the thin metal pipe P to be processed. Therefore, since a large clamping force is not applied to the processed small-diameter metal pipe P even during the second stage tensile bending process, the surface of the processed small-diameter metal pipe P has a bite or the like called a clamp mark. There is hardly anything. If the bending angle is small, the subsequent bending may not be performed.
[0012]
【The invention's effect】
As described above, the present invention is a method of pressing and bending a small-diameter metal tube with a pressure die (reaction force) in a state in which a bending roll and a clamp jig are rotated to an intermediate bending position. This is a method of bending by tension bending, so that a large clamping force is not applied to the small diameter metal tube during push bending and tension bending, and therefore, a bite that is called a concave clamp mark on the surface, etc. There is an excellent effect that it is possible to obtain a high-quality bent product with almost no crack. Furthermore, since the present invention does not require a total mold or a two-stage bending unit, the equipment cost does not increase.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing one embodiment of a bending method of a thin metal pipe according to the present invention.
FIG. 2 is a schematic perspective view showing an example of a conventional bending method of a thin metal pipe targeted by the present invention.
3 is an enlarged schematic perspective view showing a main part of the conventional bending method shown in FIG.
FIG. 4 is a schematic perspective view showing another example of a conventional bending method for a thin metal tube.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Bending apparatus 1-1 Bending roll 1-2 Clamp jig 1-3 Bend arm 1-4 Pressure die (Reaction force receiving)
P Thin metal pipe to be processed

Claims

A processing direction is set by rotating a thin metal pipe to be processed by a predetermined angle about its axis, and the thin metal pipe to be processed is held between a bending roller and a pipe clamp jig, and a reaction force is received. The bending roll and the clamping jig are rotated a predetermined angle while pressing the thin metal pipe to be processed against the peripheral surface of the bending roll in a state where the thin metal pipe is brought into contact with the thin metal pipe to be processed. In the bending method of bending and bending the workpiece thin metal pipe by moving it, before bending the workpiece thin diameter metal pipe, the workpiece thin metal tube is bent with a bending roll and a pipe. After clamping with the clamp jig, the pipe rear end is opened, and the bending roll and the pipe clamp jig are rotated at the bending angle before moving the reaction force receiver to the machining position, so that the thin metal pipe to be machined is bent. Rotate to the force receiving side and then move the reaction force receiving to the machining position Bending method of a small diameter metal tube, characterized in that bending the moved press the bending angle to be processed thin metal pipe.

The machined thin metal tube is rotated by a predetermined angle around its axis to set the machining direction. The machined thin metal tube is held between a bending roll and a pipe clamp jig, and receives a reaction force. processing position is moved to and being in contact with the workpiece diameter metal tube, the bending said bending roll and the clamp jig a predetermined angle times while pressing the workpiece small diameter metal pipe on the circumferential surface of the roll In the bending method of bending by bending the thin metal pipe to be processed and pulling the thin metal pipe to be processed by a bending roll and a pipe clamp jig, the rear end of the pipe is opened and Before moving the force receiver to the processing position, the bending roll and the pipe clamp jig are rotated at the bending angle to rotate the metal pipe to be processed to the reaction force receiving side, and then the reaction force receiver is moved to the processing position. Move the thin metal pipe to be processed by bending the bending angle. Bending method of a small diameter metal tube which the cause of the clamping jig is rotated by a predetermined angle and characterized by applying bending while pulling on the processed thin metal tube after that.