JPH0760516A - Boring device - Google Patents
Boring deviceInfo
- Publication number
- JPH0760516A JPH0760516A JP22784293A JP22784293A JPH0760516A JP H0760516 A JPH0760516 A JP H0760516A JP 22784293 A JP22784293 A JP 22784293A JP 22784293 A JP22784293 A JP 22784293A JP H0760516 A JPH0760516 A JP H0760516A
- Authority
- JP
- Japan
- Prior art keywords
- cutting tool
- main shaft
- piston
- main spindle
- tool holder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Drilling And Boring (AREA)
- Cutting Tools, Boring Holders, And Turrets (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、工作物の穴加工を行う
中ぐり装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring machine for boring a workpiece.
【0002】[0002]
【従来の技術】従来一般の中ぐり装置は、図3で示すよ
うに、主軸台1に回転可能に軸承され、ビルトインモー
タ3によって回転駆動する主軸2の先端に、一端をボル
ト5で固定され、径方向に弾性変位可能なバイトホルダ
4に刃具6を設け、主軸2の軸心に軸移動可能に貫通さ
れ、キー10によって主軸と一体回転する作動軸9の先
端に形成した傾斜カム8と前記バイトホルダ4とをピン
7を介して連繋し、作動軸9の前進軸移動により前記傾
斜カム8及びピン7を介してバイトホルダ4を径方向に
変位させ、刃具6をせり出すようになっている。2. Description of the Related Art As shown in FIG. 3, a conventional general boring device is rotatably supported by a headstock 1 and has one end fixed with a bolt 5 to the tip of a main shaft 2 which is driven to rotate by a built-in motor 3. A tool 6 provided on a tool holder 4 which is elastically displaceable in the radial direction, and an inclined cam 8 formed at the tip of an operating shaft 9 which is axially movably penetrated by the shaft center of the main shaft 2 and which rotates integrally with the main shaft by a key 10. The tool holder 4 is connected to the tool holder 4 via a pin 7, and the forward movement of the operating shaft 9 causes the tool holder 4 to be radially displaced via the inclined cam 8 and the pin 7 so that the cutting tool 6 is pushed out. There is.
【0003】前記主軸2と一体回転する作動軸9の軸移
動装置は図3の主軸2の後端に設けられた図4で示す構
造である。すなわち、前記主軸台1とは別個の支持台1
1に固定された軸受部材12に筒体13をキー14によ
って回転方向は規制され、軸方向は摺動可能に設け、こ
の筒体13の前端部に前記作動軸9の後端を軸方向は係
合し、回転方向はベアリング15で回転可能に軸承して
連結させ、筒体13の後端部にはボールネジ16に螺合
するナット18が固定され、前記ボールネジ16の回転
によりナット18を介して前記筒体13を進退移動して
作動軸9を進退移動するようになっている。The shaft moving device for the working shaft 9 which rotates integrally with the main shaft 2 has the structure shown in FIG. 4 provided at the rear end of the main shaft 2 in FIG. That is, a support base 1 separate from the headstock 1
The cylindrical body 13 is fixed to the bearing member 12 fixed to 1 by a key 14 in the rotational direction and is provided slidably in the axial direction. The rear end of the operating shaft 9 is axially provided in the front end portion of the cylindrical body 13. The nuts 18 are engaged with each other and are rotatably supported by a bearing 15 so as to be connected to each other, and a nut 18 screwed into a ball screw 16 is fixed to a rear end portion of the cylindrical body 13. The nut 18 is inserted by rotation of the ball screw 16. The cylindrical body 13 is moved forward and backward to move the operating shaft 9 forward and backward.
【0004】前記ボールネジ16は前記軸受部材12に
ベアリング17を介して軸承され、軸受部材12の後端
に取り付けられたサーボモータ19に連結されている。The ball screw 16 is supported by the bearing member 12 via a bearing 17 and is connected to a servomotor 19 mounted at the rear end of the bearing member 12.
【0005】[0005]
【発明が解決しようとする課題】上記従来の構造の中ぐ
り装置では、刃具6をせり出すためのボールネジ16部
が主軸台1とは別個の支持台11上に設置されているた
め、作動軸9と筒体13との軸芯のズレが生ずる。この
結果、主軸2を高速回転させると、主軸2の振動力が大
きくなり、加工精度が得られない問題があった。又、前
記軸芯のズレにより、作動軸9の後端を軸承しているベ
アリング15が大きく発熱し、これによる作動軸9の熱
膨張の影響により刃先の位置が変化し、加工精度が安定
しない問題があった。また、主軸2の後端に刃具6をせ
り出すための機構が連係配置されているために、全長が
長くなっている不具合もある。In the boring machine of the above-mentioned structure, the ball screw 16 for pushing out the cutting tool 6 is installed on the support base 11 which is separate from the headstock 1, so that the operating shaft 9 There is a deviation of the axial center between the cylinder body 13 and the cylinder body 13. As a result, when the main spindle 2 is rotated at a high speed, the vibration force of the main spindle 2 increases, and there is a problem that the machining accuracy cannot be obtained. Further, due to the displacement of the shaft core, the bearing 15 supporting the rear end of the operating shaft 9 generates a large amount of heat, and the thermal expansion of the operating shaft 9 causes the position of the cutting edge to change, resulting in unstable machining accuracy. There was a problem. Further, since the mechanism for pushing out the cutting tool 6 is linkedly arranged at the rear end of the main shaft 2, there is a problem that the total length is long.
【0006】[0006]
【課題を解決するための手段】本発明は上記従来の問題
に鑑みてなされたもので、その特徴とする構成は、主軸
台に回転可能に軸承されモータによって回転駆動する主
軸と、この主軸の先端に弾性支持部材を介して常に主軸
と同心位置に弾機保持され、かつ前記弾性支持部材を支
点にして径方向に変位し、先端部に取り付けられた刃具
をせり出しするバイトホルダと、ピエゾアクチュエータ
と、このピエゾアクチュエータの作動を主軸の径方向の
運動に変換するとともに前記バイトホルダ後端部に当接
可能な伝達機構とを備えたものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is characterized by a main shaft which is rotatably supported by a headstock and rotationally driven by a motor. A bite holder that is always held in a concentric position with the main shaft via an elastic support member at the tip, and is displaced in the radial direction with the elastic support member as a fulcrum to push out the cutting tool attached to the tip, and a piezo actuator. And a transmission mechanism that converts the operation of the piezo actuator into a radial movement of the main shaft and is capable of contacting the rear end of the bite holder.
【0007】[0007]
【作用】上記の構成により、ピエゾアクチュエータの印
加電圧に比例して、主軸の径方向の運動量が増大し、伝
達機構によりバイトホルダ後端部を押動して弾性支持部
材を支点にしてバイトホルダの先端部を径方向に変位さ
せ、刃具をせり出す。前記ピエゾアクチュエータの印加
電圧を切ると、弾性支持部材の弾性復元力によってバイ
トホルダは主軸と同心位置に戻される。With the above construction, the radial momentum of the main shaft increases in proportion to the applied voltage of the piezo actuator, and the rear end of the tool holder is pushed by the transmission mechanism to use the elastic support member as a fulcrum to support the tool holder. Displace the tip of the tool in the radial direction and push out the cutting tool. When the voltage applied to the piezo actuator is turned off, the bite holder is returned to the position concentric with the main shaft by the elastic restoring force of the elastic support member.
【0008】[0008]
【実施例】以下本発明の実施例を図面に基づいて説明す
る。図1において、30は主軸台、31は前記主軸台3
0に回転可能に軸承された主軸である。32は前記主軸
31の後端部に配置されたビルトインモータであり、主
軸31を回転駆動する。Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 30 is a headstock, 31 is the headstock 3
It is a main shaft rotatably supported at 0. Reference numeral 32 denotes a built-in motor arranged at the rear end of the main shaft 31, which drives the main shaft 31 to rotate.
【0009】33はバイトホルダであり、その先端の軸
部33aには刃具34が取り付けられ、主軸軸線と平行
した側面を持った後端部33bを有している。このバイ
トホルダ33は前記主軸31の先端に固定された弾性支
持部材35によって常に主軸31と同心位置に弾機保持
され、かつスリット35aを除いた部分Aを支点にして
径方向に変位可能に設けられている。この弾性支持部材
35は直径方向両側からスリット35aを設けた金属よ
りなるドーナツ鍔状部材である。A bite holder 33 has a cutting tool 34 attached to a shaft portion 33a at the tip thereof and has a rear end portion 33b having a side surface parallel to the axis of the spindle. The bite holder 33 is always held by the elastic support member 35 fixed to the tip of the main shaft 31 at a position concentric with the main shaft 31, and is displaceable in the radial direction with the portion A excluding the slit 35a as a fulcrum. Has been. The elastic support member 35 is a donut collar-shaped member made of metal and provided with slits 35a from both sides in the diametrical direction.
【0010】前記バイトホルダ33の後端部33bの主
軸31内にはシリンダ部材45とピエゾアクチュエータ
36とが軸線方向に直列配置され、前記シリンダ部材4
5には前記バイトホルダ33後端部33bの主軸軸線と
平行する側面に当接し、径方向に進退移動可能に設けら
れたピストン38と、油が封入され前記ピストン38の
背面に通じている油室39とを有している。また、前記
ピエゾアクチュエータ36の前端には前記油室39内に
封入されている油に圧力を発生させるためのピストン3
7が設けられている。前記ピストン37の径は、ピスト
ン38の径よりも大きく、これによりピストン38はピ
ストン37よりも大きなストロークが得られる。前記ピ
ストン37,38と油室39とにより、ピエゾアクチュ
エータ36の作動を主軸の径方向の運動に変換する伝達
機構が構成される。他の実施例として、伝達機構は主軸
回転軸線と直交軸線回りに旋回する「く」の字形状のレ
バーであってもよい。A cylinder member 45 and a piezo actuator 36 are arranged in series in the axial direction in the main shaft 31 of the rear end portion 33b of the bite holder 33.
Reference numeral 5 denotes a piston 38 that is in contact with a side surface of the rear end portion 33b of the bite holder 33 that is parallel to the main axis, and that is movable forward and backward in the radial direction, and oil that is filled with oil and communicates with the rear surface of the piston 38. And chamber 39. A piston 3 for generating pressure on the oil enclosed in the oil chamber 39 is provided at the front end of the piezo actuator 36.
7 is provided. The diameter of the piston 37 is larger than the diameter of the piston 38, so that the piston 38 can obtain a larger stroke than the piston 37. The pistons 37, 38 and the oil chamber 39 constitute a transmission mechanism that converts the operation of the piezo actuator 36 into a radial movement of the main shaft. As another example, the transmission mechanism may be a lever having a dogleg shape pivoting around an axis orthogonal to the main shaft rotation axis.
【0011】前記主軸31内の先端部に配置されたピエ
ゾアクチュエータ36に電圧を印加するための配線は主
軸31の軸心を貫通した穴を通し、主軸31の後端でス
リップリング40を介して外部の配線と電気的に接続し
ている。41はエンコーダを示す。The wiring for applying a voltage to the piezo actuator 36 arranged at the tip of the main shaft 31 passes through a hole penetrating the shaft center of the main shaft 31, and a slip ring 40 is provided at the rear end of the main shaft 31. It is electrically connected to external wiring. Reference numeral 41 represents an encoder.
【0012】図2は本発明の他の実施例である。この他
の実施例はピエゾアクチュエータ36と、このピエゾア
クチュエータ36で進退作動するピストン37とを主軸
31の外部に配置し、主軸31の軸心に、一端が前記シ
リンダ部材45に形成されている油室39と連通する油
路42を設け、この油路42の他端は主軸31の後端部
に設けられたメカニカルシール44に連通し、このメカ
ニカルシール44を介して前記ピエゾアクチュエータ3
のピストン37の前面と配管43によって接続した構造
である。このものは、図1のスリップリング40を有し
ないため、漏電の恐れがない。FIG. 2 shows another embodiment of the present invention. In the other embodiment, a piezo actuator 36 and a piston 37 that moves back and forth by the piezo actuator 36 are arranged outside the main shaft 31, and an oil whose one end is formed in the cylinder member 45 at the shaft center of the main shaft 31. An oil passage 42 that communicates with the chamber 39 is provided, and the other end of this oil passage 42 communicates with a mechanical seal 44 provided at the rear end of the main shaft 31, and the piezoelectric actuator 3 is connected via this mechanical seal 44.
This is a structure in which the front surface of the piston 37 of FIG. Since this does not have the slip ring 40 of FIG. 1, there is no risk of electric leakage.
【0013】上記の図1の構成において、油室39に封
入されている油に圧力が発生していないときには、弾性
支持部材35に保持されているバイトホルダ33は弾性
支持部材35のばね作用によって主軸31と同心に位置
している。In the configuration of FIG. 1 described above, when no pressure is generated in the oil enclosed in the oil chamber 39, the bite holder 33 held by the elastic supporting member 35 is caused by the spring action of the elastic supporting member 35. It is located concentrically with the main shaft 31.
【0014】刃具34のせり出しにはピエゾアクチュエ
ータ36に電圧を印加する。これによりピエゾアクチュ
エータ36の前端のピストン37が前進移動し、油室3
9に封入されている油に圧力を発生する。A voltage is applied to the piezo actuator 36 to project the cutting tool 34. As a result, the piston 37 at the front end of the piezo actuator 36 moves forward and the oil chamber 3
Pressure is generated in the oil enclosed in 9.
【0015】この油室39内の発生油圧によりバイトホ
ルダ33の後端部33bの主軸軸線と平行する側面に当
接しているピストン38を前進し、バイトホルダ33の
後端部33bを押動する。このバイトホルダ33の後端
部33bの押動で弾性支持部材35を支点にしてバイト
ホルダ33の先端部33aが径方向に変位し、刃具34
をせり出す。Due to the hydraulic pressure generated in the oil chamber 39, the piston 38, which is in contact with the side surface of the rear end portion 33b of the bite holder 33 parallel to the spindle axis, is advanced to push the rear end portion 33b of the bite holder 33. . By pushing the rear end 33b of the bite holder 33, the tip 33a of the bite holder 33 is displaced in the radial direction with the elastic support member 35 as a fulcrum, and the blade 34
Stick out.
【0016】前記刃具34のせり出し量は、ピエゾアク
チュエータ36に印加する電圧を調整することによって
制御される。すなわち、ピエゾアクチュエータ36に印
加する電圧の上昇によってピストン37の前進変位量が
増大し、それに伴いバイトホルダ33の後端部33bを
押動するピストン38の前進移動量が増大する。その結
果、バイトホルダ33の先端部33aの径方向の変位量
が大きくなり、ピエゾアクチュエータ36に印加する電
圧に比例して刃具34のせり出し位置が増大する。従っ
て、穴加工径に対応してピエゾアクチュエータ36に印
加する電圧を調整設定して適正な刃具34のせり出し位
置を制御する。The amount of protrusion of the cutting tool 34 is controlled by adjusting the voltage applied to the piezo actuator 36. That is, as the voltage applied to the piezo actuator 36 increases, the forward displacement amount of the piston 37 increases, and accordingly, the forward movement amount of the piston 38 that pushes the rear end portion 33b of the bite holder 33 increases. As a result, the amount of radial displacement of the tip portion 33a of the bite holder 33 increases, and the protruding position of the cutting tool 34 increases in proportion to the voltage applied to the piezo actuator 36. Therefore, the voltage applied to the piezo actuator 36 is adjusted and set according to the hole machining diameter to control the appropriate protruding position of the cutting tool 34.
【0017】ピエゾアクチュエータ36の印加電圧を切
ると、油室39内の容積が増大されるため油室39内の
油の圧力が降下し、弾性支持部材35のばね作用による
弾性復元力によってバイトホルダ33の後端部33bを
押動しているピストン38が後退方向に押し返され、ピ
ストン37が後退するとともにバイトホルダ33は主軸
31と同心位置に戻される。When the voltage applied to the piezo actuator 36 is cut off, the volume of the oil chamber 39 increases and the pressure of the oil in the oil chamber 39 drops. The elastic restoring force of the elastic supporting member 35 causes the bite holder. The piston 38 pushing the rear end portion 33b of 33 is pushed back in the backward direction, the piston 37 is moved backward, and the bite holder 33 is returned to the position concentric with the main shaft 31.
【0018】図2で示す他の実施例では、主軸31の外
部に配置したピエゾアクチュエータ36によるピストン
37の前進移動により、配管43及び配管43とメカニ
カルシール44を介して連通した主軸31の軸心の油路
42内の油を移動し、油室39内に封入されている油に
圧力を発生させて、前記と同様な刃具34のせり出しを
行うものである。この場合、主軸31の外部に配置した
ピエゾアクチュエータ36への電気配線の取り回しが容
易になる。In another embodiment shown in FIG. 2, the forward movement of the piston 37 by the piezo actuator 36 arranged outside the main shaft 31 causes the pipe 43 and the shaft center of the main shaft 31 communicating with the pipe 43 via the mechanical seal 44. The oil in the oil passage 42 is moved to generate a pressure in the oil enclosed in the oil chamber 39, and the blade 34 is pushed out in the same manner as described above. In this case, it becomes easy to arrange the electric wiring to the piezo actuator 36 arranged outside the spindle 31.
【0019】[0019]
【発明の効果】以上述べたように本発明は、主軸の先端
に刃具を備えたバイトホルダの先端部を弾性支持部材を
介して径方向に変位可能に保持し、ピエゾアクチュエー
タと伝達機構によって主軸の径方向の運動を発生させる
とともにバイトホルダの後端部を押動し、弾性支持部材
を支点にしてバイトホルダの先端部を径方向に変位する
ことにより刃具をせり出しするようにした構成であるか
ら、従来のように主軸後部のサーボモータ、ボールネ
ジ、作動軸及び発熱する回転軸承部を不要とし、省スペ
ース化と、主軸の高速回転時の熱変位による刃具のせり
出し精度の低下を防止できる。又、軸芯のズレがないた
め、主軸を高速回転させても主軸の振動が少なく加工精
度が向上する。As described above, according to the present invention, the tip end of the bite holder provided with a cutting tool at the tip of the spindle is held by an elastic support member so as to be displaceable in the radial direction, and the spindle is provided by a piezo actuator and a transmission mechanism. Of the cutting tool, the rear end of the cutting tool holder is pushed, and the tip of the cutting tool holder is displaced in the radial direction with the elastic supporting member as a fulcrum, so that the cutting tool is pushed out. Therefore, unlike the conventional case, the servomotor, the ball screw, the actuating shaft and the rotating shaft bearing for generating heat which are required in the rear of the main spindle are not required, so that it is possible to save space and prevent the accuracy of the protrusion of the cutting tool from being lowered due to the thermal displacement of the main spindle at high speed. Further, since there is no misalignment of the shaft core, the vibration of the main shaft is small even when the main shaft is rotated at high speed, and the machining accuracy is improved.
【図1】本発明装置の断面図FIG. 1 is a sectional view of the device of the present invention.
【図2】本発明装置の他の実施例を示す断面図FIG. 2 is a sectional view showing another embodiment of the device of the present invention.
【図3】従来装置の主軸前半分の断面図FIG. 3 is a sectional view of a front half of a spindle of a conventional device.
【図4】従来装置の主軸後半分の断面図FIG. 4 is a sectional view of the latter half of the main shaft of a conventional device.
30 主軸台 31 主軸 32 ビルトインモータ 33 バイトホルダ 34 刃具 35 弾性支持部材 36 ピエゾアクチュエータ 37 ピストン 38 ピストン 39 油室 30 Headstock 31 Main spindle 32 Built-in motor 33 Tool holder 34 Cutting tool 35 Elastic support member 36 Piezo actuator 37 Piston 38 Piston 39 Oil chamber
───────────────────────────────────────────────────── フロントページの続き (72)発明者 長澤 信寛 愛知県刈谷市朝日町1丁目1番地 豊田工 機株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuhiro Nagasawa 1-1, Asahi-cho, Kariya city, Aichi prefecture Toyota Koki Co., Ltd.
Claims (1)
って回転駆動する主軸と、この主軸の先端に弾性支持部
材を介して常に主軸と同心位置に弾機保持され、かつ前
記弾性支持部材を支点にして径方向に変位し、先端部に
取り付けられた刃具をせり出しするバイトホルダと、ピ
エゾアクチュエータと、このピエゾアクチュエータの作
動を主軸の径方向の運動に変換するとともに前記バイト
ホルダ後端部に当接可能な伝達機構とを備えたことを特
徴とする中ぐり装置。1. A main shaft that is rotatably supported by a headstock and is rotationally driven by a motor, and an elastic supporting member at the tip of the main shaft, which is always held in a concentric position with the main shaft, and the elastic supporting member is a fulcrum. And the tool holder that displaces in the radial direction and pushes out the cutting tool attached to the tip, the piezo actuator, and converts the operation of this piezo actuator into the radial movement of the main spindle, and applies it to the rear end of the tool holder. A boring device having a transmission mechanism capable of contacting.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP22784293A JPH0760516A (en) | 1993-08-23 | 1993-08-23 | Boring device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP22784293A JPH0760516A (en) | 1993-08-23 | 1993-08-23 | Boring device |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0760516A true JPH0760516A (en) | 1995-03-07 |
Family
ID=16867228
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP22784293A Pending JPH0760516A (en) | 1993-08-23 | 1993-08-23 | Boring device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0760516A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6128985A (en) * | 1996-05-10 | 2000-10-10 | Kummer Fre'res Sa Fabrique De Machines | Machine tool |
JP2006346819A (en) * | 2005-06-16 | 2006-12-28 | Denso Corp | Cutting device |
-
1993
- 1993-08-23 JP JP22784293A patent/JPH0760516A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6128985A (en) * | 1996-05-10 | 2000-10-10 | Kummer Fre'res Sa Fabrique De Machines | Machine tool |
JP2006346819A (en) * | 2005-06-16 | 2006-12-28 | Denso Corp | Cutting device |
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