JP3317419B2 - Hydraulic chuck - Google Patents
Hydraulic chuckInfo
- Publication number
- JP3317419B2 JP3317419B2 JP01356294A JP1356294A JP3317419B2 JP 3317419 B2 JP3317419 B2 JP 3317419B2 JP 01356294 A JP01356294 A JP 01356294A JP 1356294 A JP1356294 A JP 1356294A JP 3317419 B2 JP3317419 B2 JP 3317419B2
- Authority
- JP
- Japan
- Prior art keywords
- peripheral surface
- thin
- outer cylinder
- cylinder
- contact portion
- 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.)
- Expired - Lifetime
Links
Landscapes
- Gripping On Spindles (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、工作機械の主軸に装着
され種々の工具や工作物等を把持する液圧チャックに関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic chuck mounted on a main shaft of a machine tool for gripping various tools and workpieces.
【０００２】[0002]
【従来の技術】一般に、工作機械の主軸には、種々の工
具や工作物等を把持するためにチャックが装着される。
例えば、チャックはドリル，エンドミル，リール等の回
転工具を把持するために使用されたり、旋盤等の工作機
械で加工される工作物の円筒部の内周面を把持するため
に使われている。2. Description of the Related Art Generally, a chuck is mounted on a main shaft of a machine tool to hold various tools and workpieces.
For example, a chuck is used to hold a rotating tool such as a drill, an end mill, a reel, or the like, or is used to hold an inner peripheral surface of a cylindrical portion of a workpiece processed by a machine tool such as a lathe.
【０００３】かかるチャックの機構の一例として、例え
ば、実公昭６１−９６９号公報に示す如き液体チャック
が知られている。一般に、この種の液体チャックは、粘
性の高いグリースまたは非圧縮系のオイル等の作動流体
で満たされた液圧室を構成し、液圧室の一部を構成する
プランジャの押圧により作動流体に圧力を与え、それに
よって薄状筒体に圧力を加えて該薄状筒体を弾性変形さ
せるもので、工具または工作物の円筒部を把持すること
を可能にしている。[0003] As an example of such a chuck mechanism, for example, a liquid chuck as disclosed in Japanese Utility Model Publication No. 61-969 is known. In general, this type of liquid chuck constitutes a hydraulic chamber filled with a working fluid such as highly viscous grease or non-compressed oil, and is pressed to the working fluid by pressing a plunger which constitutes a part of the hydraulic chamber. A pressure is applied to the thin cylindrical body to thereby elastically deform the thin cylindrical body, so that a cylindrical portion of a tool or a workpiece can be gripped.
【０００４】[0004]
【発明が解決しようとする課題】ところが、従来の液圧
チャックにおいては、弾性変形させて工具または工作物
の円筒部を把持する薄状筒体は、剛性が不足しており、
高速精密エンドミルの加工を行なうフライス盤や高速旋
盤等の、高速で回転する工作機械では、該液圧チャック
を高速で回転すると、液圧室内に封入されているオイル
が、その遠心力で径外方へ振れるように作用し、そのた
め、オイルにより工具または工作物の円筒部に対する薄
状筒体の締付力が低下し、把持している工具等が該液圧
チャックから外れて飛ぶ虞もあり、危険性があるという
問題がある。However, in a conventional hydraulic chuck, a thin cylindrical body which elastically deforms and grips a cylindrical portion of a tool or a workpiece has insufficient rigidity.
In machine tools that rotate at high speed, such as milling machines and high-speed lathes that perform high-speed precision end mill processing, when the hydraulic chuck is rotated at high speed, the oil sealed in the hydraulic chamber is forced out of the radial direction by the centrifugal force. It acts to swing to the side, so the oil reduces the tightening force of the thin cylindrical body against the cylindrical part of the tool or workpiece, and there is a possibility that the gripped tool or the like may come off from the hydraulic chuck and fly, There is a problem of danger.
【０００５】本発明は、上述の問題点を解決するために
なされたもので、その目的は、特に、高速回転下におい
て把持している工具等に対して薄状筒体の締付力をアッ
プし、安全性を高くできる液圧チャックを提供すること
である。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to increase the tightening force of a thin cylindrical body particularly for a tool or the like gripped under high-speed rotation. Another object of the present invention is to provide a hydraulic chuck capable of improving safety.
【０００６】[0006]
【課題を解決するための手段】請求項１記載の発明は、
基端側が工作機械の主軸に装着されるチャック本体と、
チャック本体の先端側に形成された外筒と、外筒の内側
に配置され工具を内周面で把持する薄肉内筒部と、外筒
の内周面と薄肉内筒部の外周面の間に形成されるととも
に封入された作動流体で該薄肉内筒部の外周面に締付力
を与える液圧室と、液圧室内に回動自在に収容配置され
た複数の締付片とを備え、前記締付片は、外筒の内周面
に当接した外側当接部と、薄肉内筒部の外周面に当接し
た内側当接部とを有し、締付片の重心は、該締付片にお
いて外側当接部とチャック本体の軸心を結ぶ線よりも内
側当接部の反対側に位置していることを特徴とする。According to the first aspect of the present invention,
A chuck body whose base end is attached to the main shaft of the machine tool,
An outer cylinder formed on the tip side of the chuck body, a thin inner cylinder portion disposed inside the outer cylinder and holding a tool on the inner peripheral surface, and between an inner peripheral surface of the outer cylinder and an outer peripheral surface of the thin inner cylinder portion. A hydraulic chamber for applying a tightening force to the outer peripheral surface of the thin inner cylindrical portion with a working fluid sealed therein and a plurality of tightening pieces rotatably housed and disposed in the hydraulic chamber. The fastening piece has an outer abutting portion abutting on the inner peripheral surface of the outer cylinder and an inner abutting portion abutting on the outer peripheral surface of the thin inner cylindrical portion, and the center of gravity of the fastening piece is The fastening piece is located on a side opposite to the inner contact portion with respect to a line connecting the outer contact portion and the axis of the chuck body.
【０００７】請求項２記載の発明は、基端側が工作機械
の主軸に装着されるチャック本体と、チャック本体の先
端側に形成された外筒と、外筒の内側に配置され工具を
内周面で把持する薄肉内筒部と、外筒の内周面と薄肉内
筒部の外周面の間に形成されるとともに封入された作動
流体で該薄肉内筒部の外周面に締付力を与える液圧室
と、液圧室内に回動自在に収容配置された複数の締付片
とを備え、前記締付片は、外筒の内周面に当接自在の外
側当接部と、薄肉内筒部の外周面に当接自在の内側当接
部とを有し、締付片の重心は、該締付片において外側当
接部とチャック本体の軸心を結ぶ線よりも内側当接部の
反対側に位置していることを特徴とする。According to a second aspect of the present invention, there is provided a chuck body having a base end mounted on a main shaft of a machine tool, an outer cylinder formed on a distal end side of the chuck body, and a tool disposed inside the outer cylinder and having an inner periphery. A thin inner cylinder portion gripped by a surface, and a clamping force is applied to the outer peripheral surface of the thin inner cylinder portion by a working fluid sealed between the inner peripheral surface of the outer cylinder and the outer peripheral surface of the thin inner cylinder portion. A hydraulic chamber to be provided, and a plurality of tightening pieces rotatably housed and arranged in the hydraulic chamber, wherein the tightening pieces have an outer contact portion that can freely contact the inner peripheral surface of the outer cylinder, An inner contact portion which can freely contact the outer peripheral surface of the thin inner cylindrical portion, and the center of gravity of the fastening piece is located more inward than a line connecting the outer contact portion and the axis of the chuck body in the fastening piece. It is characterized by being located on the opposite side of the contact portion.
【０００８】請求項３記載の発明は、工作物の円筒部の
孔部を外周面で把持する薄肉外筒と、薄肉外筒の内側に
配置されて環状溝を有する軸部と、薄肉外筒の内周面と
軸部の環状溝の間に形成されて封入された作動流体で該
外筒の内周面に締付力を与える液圧室と、液圧室内に回
動自在に収容配置された複数の締付片とを備え、締付片
は、薄肉外筒の内周面に当接した外側当接部と、軸部の
環状溝に当接した内側当接部とを有し、締付片の重心
は、該締付片において外側当接部とチャック本体の軸心
を結ぶ線よりも内側当接部の反対側に位置していること
を特徴とする。According to a third aspect of the present invention, there is provided a thin outer cylinder for gripping a hole of a cylindrical portion of a workpiece with an outer peripheral surface, a shaft portion disposed inside the thin outer cylinder and having an annular groove, and a thin outer cylinder. A hydraulic chamber formed between the inner peripheral surface of the shaft and the annular groove of the shaft portion to apply a tightening force to the inner peripheral surface of the outer cylinder with a working fluid sealed therein; and a rotatable housing disposed in the hydraulic chamber. A plurality of tightening pieces, the tightening piece has an outer abutting portion abutting on the inner peripheral surface of the thin outer cylinder and an inner abutting portion abutting on the annular groove of the shaft portion. The center of gravity of the fastening piece is located on a side of the fastening piece opposite to the inner contacting part with respect to a line connecting the outer contact part and the axis of the chuck body.
【０００９】請求項４記載の発明は、工作物の円筒部の
孔部を外周面で把持する薄肉外筒と、薄肉外筒の内側に
配置されて環状溝を有する軸部と、薄肉外筒の内周面と
軸部の環状溝の間に形成されて封入された作動流体で該
外筒の内周面に締付力を与える液圧室と、液圧室内に回
動自在に収容配置された複数の締付片とを備え、締付片
は、薄肉外筒の内周面に当接自在の外側当接部と、軸部
の環状溝に当接自在の内側当接部とを有し、締付片の重
心は、該締付片において外側当接部とチャック本体の軸
心を結ぶ線よりも内側当接部の反対側に位置しているこ
とを特徴とする。According to a fourth aspect of the present invention, there is provided a thin outer cylinder for gripping a hole of a cylindrical portion of a workpiece with an outer peripheral surface, a shaft portion disposed inside the thin outer cylinder and having an annular groove, and a thin outer cylinder. A hydraulic chamber formed between the inner peripheral surface of the shaft and the annular groove of the shaft portion to apply a tightening force to the inner peripheral surface of the outer cylinder with a working fluid sealed therein; and a rotatable housing disposed in the hydraulic chamber. A plurality of tightening pieces, the tightening piece has an outer abutting part that can abut on the inner peripheral surface of the thin outer cylinder and an inner abutting part that can abut on the annular groove of the shaft part. Wherein the center of gravity of the fastening piece is located on a side of the fastening piece opposite to the inner contact portion with respect to a line connecting the outer contact portion and the axis of the chuck body.
【００１０】[0010]
【作用】請求項１記載の発明においては、工作機械の主
軸に液圧チャックのチャック本体の基端側が装着されて
いる。この液圧チャックの液圧室に封入された作動流体
で薄肉内筒部の外周面に締付力が与えられている。この
作動流体による締付力及び後述の締付片による締付力に
より薄肉内筒部の内周面を介して工具が把持されてい
る。According to the first aspect of the present invention, the base end of the chuck body of the hydraulic chuck is mounted on the main shaft of the machine tool. The working fluid sealed in the hydraulic chamber of the hydraulic chuck applies a clamping force to the outer peripheral surface of the thin inner cylindrical portion. The tool is gripped via the inner peripheral surface of the thin inner cylindrical portion by the tightening force of the working fluid and the tightening force of a tightening piece described later.
【００１１】締付片による締付力を説明するに、工作機
械の主軸の回転時には、遠心力を受ける締付片の重心
は、その外側当接部を支点として径外方に向けて回動す
る。同時に、締付片の内側当接部が外側当接部を支点と
して径内方に回動する。従って、締付片の内側当接部が
内筒の外周面を押圧する。この押圧力で径内方に弾性変
形した薄肉内筒部は工具に対して締付力を増加させる。To explain the tightening force of the tightening piece, when the main shaft of the machine tool rotates, the center of gravity of the tightening piece which receives centrifugal force turns radially outward with its outer abutting portion as a fulcrum. I do. At the same time, the inner contact portion of the fastening piece rotates radially inward with the outer contact portion as a fulcrum. Therefore, the inner contact portion of the fastening piece presses the outer peripheral surface of the inner cylinder. The thin inner cylinder portion elastically deformed radially inward by this pressing force increases the tightening force on the tool.
【００１２】なお、締付片の外側当接部が当接した状態
の外筒の内周面は、弾性変形する薄肉内筒部とは違って
遠心力によっても変形が防止されている。請求項２記載
の発明においては、請求項１記載の発明と同様の作用が
生じるが、次の点で相違する。即ち、請求項１記載の締
付片では、主軸の無回転時に外側当接部は外筒の内周面
に当接した状態になっており、同時に、内側当接部は薄
肉内筒部の外周面に当接した状態となっているのに対し
て、請求項２記載の締付片は、主軸の無回転時にも回動
可能に構成しているので、工作機械の主軸の回転時に、
遠心力で径外方に回動する。従って、主軸の回転時に外
側当接部は外筒の内周面に当接するとともに、内側当接
部は薄肉内筒部の外周面に当接するようになる。The inner peripheral surface of the outer cylinder in a state where the outer abutting portion of the fastening piece abuts is prevented from being deformed even by centrifugal force unlike the thin inner cylindrical portion which is elastically deformed. According to the second aspect of the invention, the same operation as that of the first aspect of the invention occurs, but the following points are different. That is, in the fastening piece according to the first aspect, the outer contact portion is in contact with the inner peripheral surface of the outer cylinder when the main shaft is not rotating, and at the same time, the inner contact portion is the thin inner cylinder portion. In contrast to being in contact with the outer peripheral surface, the fastening piece according to claim 2 is configured to be rotatable even when the main spindle is not rotating.
Rotate outward by centrifugal force. Therefore, when the main shaft rotates, the outer contact portion comes into contact with the inner peripheral surface of the outer cylinder, and the inner contact portion comes into contact with the outer peripheral surface of the thin inner cylinder portion.
【００１３】請求項３記載の発明においては、工作物の
円筒部を把持した液圧チャックは旋盤等の工作機械の主
軸に装着される。この時、液圧チャックの液圧室に封入
された作動流体で薄肉外筒の内周面に締付力が与えられ
る。この作動流体による締付力及び後述の締付片による
締付力により薄肉外筒の外周面を介して工作物の円筒部
が把持されている。According to the third aspect of the present invention, the hydraulic chuck gripping the cylindrical portion of the workpiece is mounted on a main shaft of a machine tool such as a lathe. At this time, a tightening force is applied to the inner peripheral surface of the thin outer cylinder by the working fluid sealed in the hydraulic chamber of the hydraulic chuck. The cylindrical portion of the workpiece is gripped via the outer peripheral surface of the thin outer cylinder by the tightening force of the working fluid and the tightening force of a tightening piece described later.
【００１４】締付片による締付力を説明するに、旋盤等
の工作機械の主軸の回転時には、遠心力を受ける締付片
の重心は、軸部の環状溝に当接した状態の内側当接部を
支点として径外方に向けて回動する。これにより、締付
片の外側当接部が薄肉外筒の内周面を押圧し、この押圧
力で、薄肉外筒が径外方に弾性変形する。薄肉外筒部に
より工具の把握力が増す。To explain the tightening force of the tightening piece, when the main shaft of a machine tool such as a lathe rotates, the center of gravity of the tightening piece that receives the centrifugal force is in contact with the inner groove in the state of being in contact with the annular groove of the shaft portion. It pivots radially outward with the contact portion as a fulcrum. As a result, the outer abutting portion of the fastening piece presses the inner peripheral surface of the thin outer cylinder, and the pressing force causes the thin outer cylinder to elastically deform radially outward. The thin outer cylinder increases gripping power of the tool.
【００１５】なお、締付片の内側当接部が当接した状態
の軸部の外周面は変形が防止されている。請求項４記載
の発明においては、請求項３記載の発明と同様の作用が
生じるが、次の点で相違する。即ち、請求項３記載の締
付片では、主軸の無回転時に外側当接部は薄肉外筒の内
周面に当接した状態になっており、同時に、内側当接部
は軸部の環状溝に当接した状態となっているのに対し
て、請求項４記載の締付片は、主軸の無回転時にも回動
可能に構成しているので、工作機械の主軸の回転時に、
遠心力で径外方に回動する。従って、主軸の回転時に外
側当接部は薄肉外筒の内周面に当接するとともに、内側
当接部は軸部の環状溝に当接するようになる。The outer peripheral surface of the shaft portion in a state where the inner abutting portion of the fastening piece is in contact is prevented from being deformed. According to the fourth aspect of the invention, the same operation as that of the third aspect of the invention occurs, but the following points are different. In other words, according to the third aspect of the present invention, the outer contact portion is in contact with the inner peripheral surface of the thin outer cylinder when the main shaft is not rotating, and at the same time, the inner contact portion is formed in an annular shape of the shaft portion. In contrast to being in contact with the groove, the fastening piece according to claim 4 is configured to be rotatable even when the main spindle is not rotating.
Rotate outward by centrifugal force. Therefore, when the main shaft rotates, the outer contact portion comes into contact with the inner peripheral surface of the thin outer cylinder, and the inner contact portion comes into contact with the annular groove of the shaft portion.
【００１６】[0016]
【実施例】以下、図面により本発明の実施例について説
明する。図１ないし図４は請求項１記載の発明の実施例
に係わる液圧チャックを示す。Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a hydraulic chuck according to an embodiment of the present invention.
【００１７】図１，図２において、符号１はチャック本
体で、このチャック本体１の基端側に形成されたテーパ
部１Ａは高速精密エンドミル等の加工を行なうフライス
盤（図示せず）の主軸２に装着されている。1 and 2, reference numeral 1 denotes a chuck main body, and a tapered portion 1A formed on the base end side of the chuck main body 1 has a main spindle 2 of a milling machine (not shown) for processing a high-speed precision end mill or the like. It is attached to.
【００１８】チャック本体１の先端側に外筒３が形成さ
れている。外筒３は、その肉厚寸法は大きく、充分な強
度を持っており、後述する締付片１０の外側当接部１１
による押圧力で変形しない程度となっている。外筒３に
は環状フランジ４が形成され、この環状フランジ４には
螺子孔４Ａが穿設され、この螺子孔４Ａの先端に連続し
てオイル通路５が形成されている。オイル通路５は、ク
ランク状に折れ曲がっっており、その先端５Ａは、後述
する液圧室９に開口している。螺子孔４Ａにはプラグ４
Ｂが螺子込まれている。このプラグ４Ｂでオイル通路５
に摺動自在に収容したピストン１３を押圧し、液圧室９
内のオイルに圧力を与える。An outer cylinder 3 is formed on the tip side of the chuck body 1. The outer cylinder 3 has a large thickness and sufficient strength, and has an outer contact portion 11 of a fastening piece 10 described later.
Is not deformed by the pressing force of An annular flange 4 is formed in the outer cylinder 3, a screw hole 4 </ b> A is formed in the annular flange 4, and an oil passage 5 is formed continuously from the tip of the screw hole 4 </ b> A. The oil passage 5 is bent in a crank shape, and its tip 5A is open to a hydraulic chamber 9 described later. Plug 4 is inserted into screw hole 4A.
B is screwed. With this plug 4B, the oil passage 5
The piston 13 slidably housed in the hydraulic chamber 9 is pressed.
Pressure on the oil inside.
【００１９】外筒３の内周面３Ａに内筒６の外周面が嵌
着されている。内筒６の中央部には外筒３の内側に位置
する薄肉内筒部７が形成され、薄肉内筒部７の内周面７
Ｂで工具８を締め付けて把持するようになっている。The outer peripheral surface of the inner cylinder 6 is fitted to the inner peripheral surface 3A of the outer cylinder 3. At the center of the inner cylinder 6, a thin inner cylinder 7 located inside the outer cylinder 3 is formed, and an inner peripheral surface 7 of the thin inner cylinder 7 is formed.
The tool 8 is tightened and gripped by B.
【００２０】内筒６の端部には環状鍔部６Ａが形成さ
れ、この環状鍔部６Ａに螺子６Ｂが螺子込まれて内筒６
と外筒３の固定を確実にしている。外筒３の内周面３Ａ
と薄肉内筒部７の外周面７Ａの間に液圧室９が形成され
ている。液圧室９には作動流体として非圧縮性のオイル
が封入され、このオイルは液圧室９内のオイルの圧力を
高め、薄肉内筒部７の外周面７Ａに締付力を与えるよう
になっている。An annular flange 6A is formed at an end of the inner cylinder 6, and a screw 6B is screwed into the annular flange 6A so that the inner cylinder 6A is closed.
And the outer cylinder 3 are securely fixed. Inner peripheral surface 3A of outer cylinder 3
A hydraulic pressure chamber 9 is formed between the outer peripheral surface 7 </ b> A of the thin inner cylinder portion 7 and the inner wall portion 7. The hydraulic chamber 9 is filled with incompressible oil as a working fluid, and this oil increases the pressure of the oil in the hydraulic chamber 9 and applies a tightening force to the outer peripheral surface 7 </ b> A of the thin inner cylinder 7. Has become.
【００２１】そして、液圧室９内に回動自在に複数（本
実施例では１２個）の駒からなる締付片１０が収容配置
されている。図３に示すように、締付片１０は、外筒３
の内周面３Ａに当接した外側当接部１１と、薄肉内筒部
７の外周面７Ａに当接した内側当接部１２とを有した駒
に構成されている。A tightening piece 10 composed of a plurality of (12 in this embodiment) pieces is rotatably accommodated in the hydraulic pressure chamber 9. As shown in FIG. 3, the fastening piece 10 is
The outer contact portion 11 is in contact with the inner peripheral surface 3A, and the inner contact portion 12 is in contact with the outer peripheral surface 7A of the thin inner cylindrical portion 7.
【００２２】締付片１０は、底部１０Ａと、底部１０Ａ
から若干量上がった逃部１０Ｂと、第１縁部１０Ｃと、
第１縁部１０Ｃに連続する第１傾斜部１０Ｄと、第１傾
斜部１０Ｄと所定の角度をなす第２傾斜部１０Ｅと、第
２縁部１０Ｆとから構成されている。第１傾斜部１０Ｄ
と第２傾斜部１０Ｅの稜線が前記外側当接部１１とな
り、第２縁部１０Ｆと底部１０Ａの稜線が前記内側当接
部１２となっている。The fastening piece 10 has a bottom 10A and a bottom 10A.
The relief portion 10B slightly raised from the first edge portion 10C,
It comprises a first inclined portion 10D continuous with the first edge portion 10C, a second inclined portion 10E forming a predetermined angle with the first inclined portion 10D, and a second edge portion 10F. 1st inclined part 10D
The ridge line of the second inclined portion 10E is the outer contact portion 11, and the ridge line of the second edge portion 10F and the bottom portion 10A is the inner contact portion 12.
【００２３】締付片１０の重心１４の位置は、外側当接
部１１とチャック本体１の軸心１Ｂを結ぶ線Ｌ１よりも
内側当接部１２の反対側に位置している。しかして、本
実施例においては、工作機械の主軸２に液圧チャックの
チャック本体１のテーパ部１Ａが装着されている。この
液圧チャックの液圧室９に封入されたオイルで薄肉内筒
部７の外周面７Ａに締付力が与えられ、このオイルによ
る締付力及び後述の締付片１０による締付力により薄肉
内筒部７の内周面７Ｂを介して工具８が把持されてい
る。The position of the center of gravity 14 of the fastening piece 10 is located on the opposite side of the inner contact portion 12 with respect to the line L1 connecting the outer contact portion 11 and the axis 1B of the chuck body 1. In this embodiment, the tapered portion 1A of the chuck body 1 of the hydraulic chuck is mounted on the main shaft 2 of the machine tool. Tightening force is applied to the outer peripheral surface 7A of the thin-walled inner cylindrical portion 7 by the oil sealed in the hydraulic chamber 9 of the hydraulic chuck, and the tightening force by the oil and the tightening force by the tightening piece 10 described later are applied. The tool 8 is gripped via the inner peripheral surface 7B of the thin inner cylindrical portion 7.
【００２４】そして、締付片１０による締付力を説明す
るに、図４に示すように、主軸２の無回転時には、当該
液圧チャックの締付片１０は実線Ｘで示す位置にある
が、主軸２の回転時には、遠心力Ｅで、締付片１０が径
外方に変位して２点鎖線Ｙで示した状態になっている。
遠心力Ｅを受ける締付片１０の重心１４の位置は、その
外側当接部１１を支点として径外方に向けて回動する。
同時に、締付片１０の内側当接部１２が外側当接部１１
を支点として径内方に回動する。従って、締付片１０の
内側当接部１２が薄肉内筒部７の外周面７Ａを押圧し、
この押圧力Ｆで薄肉内筒部７が径内方に弾性変形する。
この弾性変形した薄肉内筒部７で工具８に対する締付力
が増す。To explain the tightening force of the tightening piece 10, as shown in FIG. 4, when the main shaft 2 is not rotating, the tightening piece 10 of the hydraulic chuck is at a position indicated by a solid line X. When the main shaft 2 rotates, the fastening piece 10 is displaced radially outward due to the centrifugal force E, and is in a state shown by a two-dot chain line Y.
The position of the center of gravity 14 of the tightening piece 10 receiving the centrifugal force E rotates radially outward with the outer contact portion 11 as a fulcrum.
At the same time, the inner contact portion 12 of the fastening piece 10 is
Is pivoted radially inward about the fulcrum. Therefore, the inner contact portion 12 of the fastening piece 10 presses the outer peripheral surface 7A of the thin inner cylinder portion 7,
With this pressing force F, the thin inner cylinder portion 7 is elastically deformed radially inward.
The tightening force on the tool 8 is increased by the elastically deformed thin inner cylindrical portion 7.
【００２５】なお、締付片１０の外側当接部１１が当接
した状態の外筒３の内周面３Ａは遠心力Ｅによっても変
形が防止されている。以上の如き構成によれば、工作機
械の主軸２の回転時には、遠心力Ｅにより生じた押圧力
Ｆで、締付片１０の外側当接部１１が薄肉内筒部７の外
周面７Ａを押圧するので、薄肉内筒部７が径内方に弾性
変形し、工具８に対して液体による締付力に加えて締付
片１０による締付力を与えることができる。The inner peripheral surface 3A of the outer cylinder 3 in a state where the outer abutting portion 11 of the fastening piece 10 abuts is also prevented from being deformed by the centrifugal force E. According to the above configuration, when the main shaft 2 of the machine tool rotates, the outer contact portion 11 of the fastening piece 10 presses the outer peripheral surface 7A of the thin inner cylinder portion 7 with the pressing force F generated by the centrifugal force E. Therefore, the thin inner cylindrical portion 7 is elastically deformed inward in the radial direction, so that the tool 8 can be provided with the tightening force of the tightening piece 10 in addition to the tightening force of the liquid.
【００２６】従って、高速回転する工作機械の主軸２
に、当該液圧チャックを装着して用いる場合、薄肉内筒
部７はオイルの圧力による締付力が低下しても、この締
付力に、締付片１０による機械的な締付力を加え、全体
としての締付力を増加させることができる。Therefore, the spindle 2 of the machine tool rotating at high speed
When the hydraulic chuck is attached and used, even if the thin inner cylinder portion 7 reduces the tightening force due to the oil pressure, the mechanical tightening force of the tightening piece 10 is added to this tightening force. In addition, the overall tightening force can be increased.
【００２７】この結果、特に、高速回転下で、把持して
いる工具８に対して締付力をアップし、締付力の低下に
よる工具８のスリップを防止し、安全性を高くできるこ
とができる。As a result, especially under high-speed rotation, the tightening force of the gripping tool 8 is increased, the slip of the tool 8 due to the decrease of the tightening force is prevented, and the safety can be improved. .
【００２８】また、薄肉内筒部７の剛性不足によりいわ
ゆる「ビビリ現象」と称されている微振動を防止でき
る。高速回転下での工具８の把持を確実にできる。な
お、本実施例においては、締付片の例として図３に示す
形状の駒を例に挙げており、締付片の数は１２個となっ
ているが、かかる個数に限定されないことは勿論であ
る。少なくとも２個あれば良い。締付片の数に従ってそ
の形状も相違することになる。Further, a minute vibration called so-called "chatter phenomenon" can be prevented due to insufficient rigidity of the thin inner cylinder portion 7. The tool 8 can be reliably held under high-speed rotation. In the present embodiment, a piece having the shape shown in FIG. 3 is taken as an example of the fastening piece, and the number of the fastening pieces is 12, but it is needless to say that the number is not limited to this. It is. At least two are sufficient. The shape will also differ according to the number of fastening pieces.
【００２９】また、本実施例においては、締付片１０の
外側当接部１１は第１傾斜部１０Ｄと第２傾斜部１０Ｅ
の稜線で形成され、且つ、締付片１０の内側当接部１２
は、第２縁部１０Ｆと底部１０Ａの稜線で形成されてい
るが、外側当接部及び内側当接部の形状はかかる形状に
限定されることなく、外側当接部を支点とした「てこ」
の原理で遠心力Ｅを内側当接部に伝達できるようにすれ
ば良く、外側当接部，内側当接部を例えば突起部で構成
することもできる。Further, in this embodiment, the outer contact portion 11 of the fastening piece 10 has the first inclined portion 10D and the second inclined portion 10E.
And the inner contact portion 12 of the fastening piece 10
Is formed by the ridge line of the second edge 10F and the bottom 10A, but the shape of the outer contact portion and the inner contact portion is not limited to such a shape, and the "lever lever""
The centrifugal force E may be transmitted to the inner contact portion according to the principle described above, and the outer contact portion and the inner contact portion may be constituted by, for example, protrusions.
【００３０】さらに、本実施例においては、液圧室９内
で締付片１０は位置決めされていないが、例えば、図３
の締付片１０の両端面にそれぞれシャフト１６，１６を
設け、チャック本体１の形成した溝状の受部にそれぞれ
支持させることにより締付片１０の位置決めをし、締付
片１０の回動を確実にすることもできる。Further, in the present embodiment, the fastening piece 10 is not positioned in the hydraulic chamber 9;
Shafts 16 and 16 are provided on both end surfaces of the tightening piece 10, respectively, and supported by the groove-shaped receiving portions formed in the chuck body 1 to position the tightening piece 10 and to rotate the tightening piece 10. Can be ensured.
【００３１】そして、本実施例の締付片１０において
は、外側当接部１１は外筒３の内周面３Ａに当接した状
態になっており、同時に、内側当接部１２は薄肉内筒部
７の外周面７Ａに当接した状態となっているが、締付片
を、主軸２の無回転時にも回動可能に構成し、主軸２の
回転時に外側当接部を外筒３の内周面３Ａに当接させる
とともに、内側当接部を薄肉内筒部７の外周面７Ａに当
接させるようにすることもできる。In the fastening piece 10 of the present embodiment, the outer contact portion 11 is in contact with the inner peripheral surface 3A of the outer cylinder 3, and at the same time, the inner contact portion 12 is in the thin inner portion. Although it is in contact with the outer peripheral surface 7 </ b> A of the cylindrical portion 7, the fastening piece is configured to be rotatable even when the main shaft 2 is not rotating, and the outer abutting portion is configured to rotate when the main shaft 2 rotates. And the inner contact portion can be brought into contact with the outer peripheral surface 7A of the thin inner cylindrical portion 7.
【００３２】そして、また、本実施例においては、作動
流体として非圧縮系のオイルを用いているが、これに限
定されることなく、例えば、グリース等の粘性流体を用
いることもできる。In the present embodiment, non-compressed oil is used as the working fluid. However, the working fluid is not limited to this, and a viscous fluid such as grease may be used.
【００３３】そして、さらに、図３に示すように、例え
ば、締付片１０の第１縁部１０Ｃ付近に、軸線方向に沿
った比重の重い鉛棒１５からなる錘を充填または埋め込
むこともできる。これにより締付片１０に対して遠心力
Ｅを受け易くすることができる。Further, as shown in FIG. 3, for example, a weight composed of a lead rod 15 having a high specific gravity along the axial direction can be filled or embedded in the vicinity of the first edge 10C of the fastening piece 10. . As a result, the fastening piece 10 can be easily subjected to the centrifugal force E.
【００３４】図５ないし図７は請求項３記載の発明の実
施例に係わる液圧チャックを示す。この液圧チャック
は、工作物の円筒部の孔部を把持するもので、マンドレ
ルに適用した例を説明する。[0034] FIGS. 5-7 show a hydraulic chuck according to an embodiment of the invention of claim 3, wherein. This hydraulic chuck grips a hole in a cylindrical portion of a workpiece, and an example in which the hydraulic chuck is applied to a mandrel will be described.
【００３５】図において、符号２１はチャック本体で、
このチャック本体２１の基端側に形成されたシャンク部
２１Ａは、旋盤等の工作機械（図示せず）の主軸２２に
装着されている。In the drawing, reference numeral 21 denotes a chuck body,
A shank portion 21A formed on the base end side of the chuck body 21 is mounted on a main shaft 22 of a machine tool (not shown) such as a lathe.
【００３６】チャック本体２１の先端側に断面円形の軸
部２３が形成され、軸部２３の外側に薄肉外筒２４が配
置されている。軸部２３の中央部には環状溝２５が形成
され、薄肉外筒２４の外周面２４Ａで工作物の円筒部２
６の孔部を締め付けて把持するようになっている。軸部
２３の外周面２３Ｅに薄肉外筒２４の内周面２４Ｂが嵌
着されている。環状溝２５と薄肉外筒２４の内周面２４
Ｂで囲まれた空間は液圧室２７として形成されている。
液圧室２７には作動流体として非圧縮性のオイルが封入
されている。A shaft section 23 having a circular cross section is formed on the distal end side of the chuck body 21, and a thin outer cylinder 24 is disposed outside the shaft section 23. An annular groove 25 is formed at the center of the shaft portion 23, and the cylindrical portion 2 of the workpiece is
The hole 6 is tightened and gripped. The inner peripheral surface 24B of the thin outer cylinder 24 is fitted to the outer peripheral surface 23E of the shaft portion 23. Annular groove 25 and inner peripheral surface 24 of thin outer cylinder 24
The space surrounded by B is formed as a hydraulic chamber 27.
The hydraulic chamber 27 is filled with incompressible oil as a working fluid.
【００３７】軸部２３のシャンク部２１Ａの端面には螺
子孔２３Ａが穿設され、この螺子孔２３Ａの先端に連続
してオイル通路２８が形成されている。オイル通路２８
は、軸部２３の軸線方向に沿っており、途中で曲がり、
その先端２８Ａは、液圧室２７に開口している。螺子孔
２３Ａにはプラグ２３Ｂが螺子込まれている。また、オ
イル通路２８内には、プラグ２３Ｂの先端に当接して剛
球２９Ａ及びピストン２９Ｂが収容されている。プラグ
２３Ｂを締め付けることにより、ピストン２９Ｂを介し
てオイル通路２８内のオイルに圧力が与えられる。これ
により、液圧室２７内のオイルの圧力を高め、薄肉外筒
２４の内周面２４Ｂに締付力を与えるようになってい
る。A screw hole 23A is formed in the end face of the shank portion 21A of the shaft portion 23, and an oil passage 28 is formed continuously from the tip of the screw hole 23A. Oil passage 28
Is along the axial direction of the shaft portion 23, is bent in the middle,
The tip 28A is open to the hydraulic chamber 27. A plug 23B is screwed into the screw hole 23A. Further, a hard ball 29A and a piston 29B are accommodated in the oil passage 28 in contact with the tip of the plug 23B. By tightening the plug 23B, pressure is applied to the oil in the oil passage 28 via the piston 29B. Thereby, the pressure of the oil in the hydraulic chamber 27 is increased, and a tightening force is applied to the inner peripheral surface 24 </ b> B of the thin outer cylinder 24.
【００３８】同様に、軸部２３の先端側２１Ｂの端面に
は螺子孔２３Ｃが穿設され、この螺子孔２３Ｃの先端に
連続してオイル通路３０が形成されている。オイル通路
３０は、軸線方向に沿っており、途中から直角に曲がり
その先端３０Ｃは、液圧室２７に開口している。螺子孔
２３Ｃにはプラグ２３Ｄが螺子込まれている。Similarly, a screw hole 23C is formed in the end face of the tip side 21B of the shaft portion 23, and an oil passage 30 is formed continuously from the tip of the screw hole 23C. The oil passage 30 extends in the axial direction, bends at a right angle from the middle, and has a distal end 30 </ b> C opening to the hydraulic pressure chamber 27. A plug 23D is screwed into the screw hole 23C.
【００３９】また、オイル通路３０内には、プラグ２３
Ｄの先端に当接して剛球３０Ａ及びピストン３０Ｂが収
容されている。プラグ２３Ｄを締め付けることにより、
ピストン３０Ｂ及び剛球３０Ａを介してオイル通路３０
内のオイルに圧力が与えられる。これにより、液圧室２
７内のオイルの圧力を高め、薄肉外筒２４の内周面２４
Ｂに締付力を与えるようになっている。In the oil passage 30, the plug 23
The rigid ball 30A and the piston 30B are housed in contact with the tip of D. By tightening the plug 23D ,
Oil passage 30 is provided via piston 30B and hard ball 30A.
Pressure is applied to the oil inside. Thereby, the hydraulic chamber 2
7 to increase the pressure of the oil in the inner peripheral surface 24 of the thin outer cylinder 24.
B is to be tightened.
【００４０】そして、液圧室２７内に回動自在に複数
（本実施例では１２個）の駒からなる締付片３１が収容
配置されている。図７に示すように、締付片３１は、薄
肉外筒２４の内周面２４Ｂに当接した外側当接部３２
と、軸部２３の環状溝２５に当接した内側当接部３３と
を有した駒に構成されている。A plurality of (twelve in this embodiment) locking pieces 31 are rotatably accommodated in the hydraulic chamber 27. As shown in FIG. 7, the fastening piece 31 includes an outer contact portion 32 that contacts the inner peripheral surface 24 </ b> B of the thin outer cylinder 24.
And a piece having an inner contact portion 33 in contact with the annular groove 25 of the shaft portion 23.
【００４１】締付片３１は、底部３１Ａと、底部３１Ａ
から若干量上がった逃部３１Ｂと、第１縁部３１Ｃと、
第１縁部３１Ｃに連続する第１傾斜部３１Ｄと、第１傾
斜部３１Ｄと所定の角度をなす第２傾斜部３１Ｅと、第
２縁部３１Ｆとから構成されている。第１傾斜部３１Ｄ
と第２傾斜部３１Ｅの稜線が前記外側当接部３２とな
り、第２縁部３１Ｆと底部３１Ａの稜線が前記内側当接
部３３となっている。The fastening piece 31 has a bottom 31A and a bottom 31A.
Escape portion 31B slightly raised from the first edge portion 31C,
It is composed of a first inclined portion 31D that is continuous with the first edge portion 31C, a second inclined portion 31E that forms a predetermined angle with the first inclined portion 31D, and a second edge portion 31F. 1st inclined part 31D
The ridge line of the second inclined portion 31E is the outer contact portion 32, and the ridge line of the second edge portion 31F and the bottom portion 31A is the inner contact portion 33.
【００４２】締付片３１の重心３５の位置は、外側当接
部３２とチャック本体２１の軸心２１Ｃを結ぶ線Ｌ２よ
りも内側当接部３３の反対側に位置している。しかし
て、本実施例においては、旋盤等の工作機械の主軸２２
に当該液圧チャックのチャック本体２１のシャンク部２
１Ａが装着される。この液圧チャックの液圧室９に封入
されたオイルで薄肉外筒２４の内周面２４Ｂに締付力が
与えられ、このオイルによる締付力及び後述の締付片３
１による締付力により薄肉外筒２４の外周面２４Ａを介
して工作物の円筒部２６が把持されている。The position of the center of gravity 35 of the fastening piece 31 is located on the opposite side of the inner contact portion 33 with respect to the line L2 connecting the outer contact portion 32 and the axis 21C of the chuck body 21. In this embodiment, the main shaft 22 of the machine tool such as a lathe is used.
The shank 2 of the chuck body 21 of the hydraulic chuck
1A is attached. Tightening force is applied to the inner peripheral surface 24B of the thin outer cylinder 24 by the oil sealed in the hydraulic chamber 9 of the hydraulic chuck.
1, the cylindrical portion 26 of the workpiece is gripped via the outer peripheral surface 24A of the thin outer cylinder 24.
【００４３】締付片３１による締付力を説明するに、締
付片３１の内側当接部３３が当接した状態の軸部２３の
環状溝２５は遠心力Ｅによっても変形が防止されてい
る。そこで、図６に示すように、旋盤等の工作機械の主
軸２２の回転時には、遠心力Ｅを受ける締付片３１の重
心３５は、その内側当接部３３を支点として径外方に向
けて回動する。同時に、締付片３１の外側当接部３２が
内側当接部３３を支点として径外方に回動する。これに
より、締付片３１の外側当接部３２が薄肉外筒２４の内
周面２４Ｂを押圧し、この押圧力Ｆで、薄肉外筒２４が
径外方に弾性変形し、薄肉外筒２４で工作物の円筒部２
６の孔部に対する締付力が増す。To explain the tightening force of the tightening piece 31, the annular groove 25 of the shaft portion 23 in a state where the inner abutting portion 33 of the tightening piece 31 is in contact is prevented from being deformed even by the centrifugal force E. I have. Therefore, as shown in FIG. 6, when the main shaft 22 of a machine tool such as a lathe rotates, the center of gravity 35 of the tightening piece 31 receiving the centrifugal force E is directed radially outward with the inner contact portion 33 as a fulcrum. Rotate. At the same time, the outer contact portion 32 of the fastening piece 31 rotates radially outward with the inner contact portion 33 as a fulcrum. As a result, the outer contact portion 32 of the fastening piece 31 presses the inner peripheral surface 24B of the thin outer cylinder 24. With this pressing force F, the thin outer cylinder 24 elastically deforms radially outward, and the thin outer cylinder 24 The cylindrical part 2 of the workpiece
The tightening force on the hole 6 increases.
【００４４】以上の如き構成によれば、旋盤等の工作機
械の主軸２２の回転時には、遠心力Ｅで、締付片３１の
外側当接部１１が薄肉外筒２４の内周面２４Ｂを押圧す
るので、径外方に弾性変形した薄肉外筒２４で工作物の
円筒部２６の孔部に対する締付力を増すことができる。According to the above configuration, when the main shaft 22 of a machine tool such as a lathe rotates, the outer contact portion 11 of the fastening piece 31 presses the inner peripheral surface 24B of the thin outer cylinder 24 by the centrifugal force E. Therefore, the tightening force against the hole of the cylindrical portion 26 of the workpiece can be increased by the thin outer cylinder 24 elastically deformed radially outward.
【００４５】従って、高速回転する旋盤等の工作機械の
主軸２２に、当該液圧チャックを装着して用いる場合、
薄肉外筒２４は液体の圧力による締付力が低下しても、
この締付力に、締付片３１による機械的な締付力を加
え、全体としての締付力を増加させることができる。Accordingly, when the hydraulic chuck is mounted on the main shaft 22 of a machine tool such as a lathe that rotates at a high speed and used,
Even if the tightening force due to the pressure of the liquid is reduced,
A mechanical tightening force by the tightening piece 31 is added to this tightening force, so that the overall tightening force can be increased.
【００４６】この結果、特に、高速回転下で、把持して
いる工作物の円筒部２６等に対して締付力をアップし、
締付力の低下による工作物の円筒部２６のスリップを防
止し、安全性を高くできることができる。As a result, in particular, under high-speed rotation, the tightening force on the cylindrical portion 26 of the workpiece being gripped is increased,
Slip of the cylindrical portion 26 of the workpiece due to a decrease in the tightening force can be prevented, and safety can be improved.
【００４７】また、薄肉外筒２４の剛性不足によりいわ
ゆる「ビビリ現象」と称されている微振動を防止でき
る。高速回転下での工作物の円筒部２６等の把持を確実
にできる。Further, a minute vibration called so-called "chatter phenomenon" due to insufficient rigidity of the thin outer cylinder 24 can be prevented. It is possible to reliably hold the cylindrical portion 26 and the like of the workpiece under high-speed rotation.
【００４８】なお、本実施例においては、締付片の例と
して図７に示す形状の駒を例に挙げており、締付片の数
は１２個となっているが、かかる個数に限定されないこ
とは勿論である。少なくとも２個あれば良い。締付片の
数に従ってその形状も相違することになる。In this embodiment, a piece having the shape shown in FIG. 7 is taken as an example of the fastening piece, and the number of the fastening pieces is 12, but the number is not limited to this. Of course. At least two are sufficient. The shape will also differ according to the number of fastening pieces.
【００４９】また、本実施例においては、締付片３１の
外側当接部３２は第１傾斜部３１Ｄと第２傾斜部３１Ｅ
の稜線で形成され、且つ、内側当接部３３は、第２縁部
３１Ｆと底部３１Ａの稜線で形成されているが、外側当
接部及び内側当接部の形状はかかる形状に限定されるこ
となく、内側当接部を支点としたてこの原理で遠心力Ｅ
を外側当接部に伝達できるようにすれば良く、外側当接
部，内側当接部を例えば、突起部で構成することもでき
る。Further, in this embodiment, the outer contact portion 32 of the fastening piece 31 has the first inclined portion 31D and the second inclined portion 31E.
And the inner contact portion 33 is formed by the ridge line of the second edge portion 31F and the bottom portion 31A, but the shapes of the outer contact portion and the inner contact portion are limited to such shapes. The centrifugal force E is based on the principle of leverage with the inner contact portion as a fulcrum.
May be transmitted to the outer contact portion, and the outer contact portion and the inner contact portion may be constituted by, for example, protrusions.
【００５０】さらに、本実施例においては、液圧室９内
で締付片３１は位置決めされていないが、例えば、図７
の締付片３１の両端面にそれぞれシャフト３４，３４を
設け、軸部２３の溝状の受部２３Ｆ，２３Ｆ（１か所の
み図示）にそれぞれ支持させることにより締付片３１の
位置決めをし、締付片３１の回動を確実にすることもで
きる。Further, in the present embodiment, the fastening piece 31 is not positioned in the hydraulic chamber 9;
Shafts 34, 34 are provided on both end surfaces of the tightening piece 31 respectively, and are supported by groove-shaped receiving portions 23F, 23F (only one portion is shown) of the shaft portion 23, thereby positioning the tightening piece 31. In addition, the rotation of the fastening piece 31 can be ensured.
【００５１】そして、本実施例の締付片３１において
は、外側当接部３２は薄肉外筒２４の内周面２４Ｂに当
接した状態になっており、同時に、内側当接部３３は軸
部２３の環状溝２５に当接した状態となっているが、締
付片を、主軸２２の無回転時にも回動可能に構成し、主
軸２２の回転時に外側当接部を薄肉外筒２４の内周面２
４Ｂに当接させるとともに、内側当接部を軸部２３の環
状溝２５に当接させるようにすることもできる。In the fastening piece 31 of this embodiment, the outer contact portion 32 is in contact with the inner peripheral surface 24B of the thin outer cylinder 24, and at the same time, the inner contact portion 33 is Although it is in a state of contact with the annular groove 25 of the portion 23, the fastening piece is configured to be rotatable even when the main shaft 22 is not rotating, and the outer contact portion is formed with a thin outer cylinder 24 when the main shaft 22 rotates. Inner peripheral surface 2
4B, and the inner contact portion may contact the annular groove 25 of the shaft portion 23.
【００５２】そして、また、本実施例においては、作動
流体として非圧縮系のオイルを用いているが、これに限
定されることなく、例えば、グリース等の粘性流体を用
いることもできる。In the present embodiment, non-compressed oil is used as the working fluid. However, the working fluid is not limited to this, and a viscous fluid such as grease may be used.
【００５３】そして、さらに、図７に示すように、例え
ば、締付片３１の第１縁部３１Ｃ付近に、軸線方向に沿
った比重の重い鉛棒３６からなる錘を充填または埋め込
むこともできる。これにより締付片３１に対して遠心力
Ｅを受け易くすることができる。Further, as shown in FIG. 7, for example, a weight made of a lead rod 36 having a high specific gravity along the axial direction can be filled or embedded near the first edge 31C of the fastening piece 31. . This makes it easier for the fastening piece 31 to receive the centrifugal force E.
【００５４】[0054]
【発明の効果】以上説明したように、請求項１記載の発
明によれば、工作機械の主軸の回転時には、遠心力によ
り生じた押圧力で、締付片の内側当接部が薄肉内筒部の
外周面を押圧するので、薄肉内筒部が径内方に弾性変形
し、工具に対して液体による締付力に加えて締付片によ
る締付力を与えることができる。As described above, according to the first aspect of the present invention, when the main shaft of the machine tool is rotated, the inner contact portion of the tightening piece is thinned by the pressing force generated by the centrifugal force. Since the outer peripheral surface of the portion is pressed, the thin inner cylindrical portion is elastically deformed radially inward, so that the tool can be given a clamping force by the clamping piece in addition to the clamping force by the liquid.
【００５５】従って、高速回転する工作機械の主軸に、
当該液圧チャックを装着して用いる場合、薄肉内筒部は
液体の圧力による締付力が低下しても、この締付力に、
締付片による機械的な締付力を加え、全体としての締付
力を増加させることができる。Therefore, the main shaft of a machine tool rotating at high speed has:
When the hydraulic chuck is attached and used, the thin inner cylinder portion is reduced in the tightening force due to the pressure of the liquid even if the tightening force is reduced.
By applying a mechanical tightening force by the tightening piece, the overall tightening force can be increased.
【００５６】この結果、特に、高速回転下で、把持して
いる工具に対して締付力をアップし、締付力の低下によ
る工具のスリップを防止し、安全性を高くできることが
できる。As a result, especially under high-speed rotation, the tightening force of the gripped tool is increased, the slip of the tool due to the decrease of the tightening force is prevented, and the safety can be improved.
【００５７】また、薄肉内筒部の剛性不足によりいわゆ
る「ビビリ現象」と称されている微振動を防止できる。
高速回転下での工具の把持を確実にできる。また、請求
項２記載の発明によれば、請求項１記載の発明と同様の
効果を奏する。Further, it is possible to prevent a minute vibration referred to as a so-called "chatter phenomenon" due to insufficient rigidity of the thin inner cylinder portion.
The gripping of the tool under high-speed rotation can be ensured. According to the second aspect of the invention, the same effect as the first aspect of the invention can be obtained.
【００５８】また、請求項３記載の発明によれば、旋盤
等の工作機械の主軸の回転時には、遠心力で、締付片の
外側当接部が薄肉外筒の内周面を押圧するので、径外方
に弾性変形した薄肉外筒で工作物の円筒部の孔部に対す
る締付力を増すことができる。According to the third aspect of the present invention, when the main shaft of a machine tool such as a lathe rotates, the outer contact portion of the fastening piece presses the inner peripheral surface of the thin outer cylinder by centrifugal force. The thin outer cylinder elastically deformed radially outward can increase the tightening force on the hole of the cylindrical portion of the workpiece.
【００５９】従って、高速回転する旋盤等の工作機械の
主軸に、当該液圧チャックを装着して用いる場合、薄肉
外筒は液体の圧力による締付力が低下しても、この締付
力に、締付片による機械的な締付力を加え、全体として
の締付力を増加させることができる。Therefore, when the hydraulic chuck is mounted on the main shaft of a machine tool such as a lathe that rotates at high speed, the thin outer cylinder can reduce this tightening force even if the tightening force is reduced by the pressure of the liquid. In addition, a mechanical tightening force by the tightening pieces can be applied to increase the overall tightening force.
【００６０】この結果、特に、高速回転下で、把持して
いる工作物の円筒部等に対して締付力をアップし、締付
力の低下による工作物の円筒部のスリップを防止し、安
全性を高くできることができる。As a result, especially under high-speed rotation, the clamping force is increased with respect to the cylindrical portion or the like of the workpiece being gripped, thereby preventing the cylindrical portion of the workpiece from slipping due to a decrease in the clamping force. Safety can be improved.
【００６１】また、薄肉外筒の剛性不足によりいわゆる
「ビビリ現象」と称されている微振動を防止できる。高
速回転下での工作物の円筒部等の把持を確実にできる。
また、請求項４記載の発明によれば、請求項３記載の発
明と同様の効果を奏する。Further, it is possible to prevent micro vibration called so-called "chatter phenomenon" due to insufficient rigidity of the thin outer cylinder. It is possible to reliably hold a cylindrical portion or the like of a workpiece under high-speed rotation.
According to the fourth aspect of the invention, the same effect as the third aspect of the invention can be obtained.
【図１】請求項１記載の発明に係わる液圧チャックの縦
断面図である。FIG. 1 is a longitudinal sectional view of a hydraulic chuck according to the first embodiment.
【図２】図１のＩ−Ｉ断面で切断した断面図である。FIG. 2 is a cross-sectional view taken along the line II of FIG. 1;
【図３】図１の締付片の外観図である。FIG. 3 is an external view of a fastening piece of FIG. 1;
【図４】図１の締付片の作動状態説明図である。FIG. 4 is an explanatory view of an operation state of a fastening piece of FIG. 1;
【図５】請求項３記載の発明に係わる液圧チャックの縦
断面図である。FIG. 5 is a longitudinal sectional view of a hydraulic chuck according to the third aspect of the present invention.
【図６】図５のII−II断面で切断した断面図である。6 is a cross-sectional view taken along the line II-II of FIG.
【図７】図５の締付片の外観図である。FIG. 7 is an external view of a fastening piece of FIG. 5;
１ チャック本体 １Ｂ 軸心 ２ 主軸 ３ 外筒 ３Ａ 内周面 ７ 薄肉内筒部 ７Ａ 外周面 ７Ｂ 内周面 ８ 工具 ９ 液圧室 １０ 締付片 １１ 外側当接部 １２ 内側当接部 １４ 重心 ２１ チャック本体 ２１Ｃ 軸心 ２２ 主軸 ２３ 軸部 ２４ 薄肉外筒 ２４Ａ 外周面 ２４Ｂ 内周面 ２５ 環状溝 ２６ 円筒部 ２７ 液圧室 ３１ 締付片 ３２ 外側当接部 ３３ 内側当接部 Ｌ１ 線 Ｌ２ 線 DESCRIPTION OF SYMBOLS 1 Chuck main body 1B Shaft center 2 Main shaft 3 Outer cylinder 3A Inner peripheral surface 7 Thin inner cylindrical part 7A Outer peripheral surface 7B Inner peripheral surface 8 Tool 9 Hydraulic chamber 10 Tightening piece 11 Outer contact part 12 Inner contact part 14 Center of gravity 21 Chuck body 21C Shaft center 22 Main shaft 23 Shaft part 24 Thin outer cylinder 24A Outer peripheral surface 24B Inner peripheral surface 25 Annular groove 26 Cylindrical part 27 Hydraulic chamber 31 Tightening piece 32 Outer contact part 33 Inner contact part L1 line L2 line
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) B23B 31/117 610 B23B 31/14 B23B 31/40 B23B 31/02 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) B23B 31/117 610 B23B 31/14 B23B 31/40 B23B 31/02
Claims (4)
ャック本体と、 チャック本体の先端側に形成された外筒と、 外筒の内側に配置され工具を内周面で把持する薄肉内筒
部と、 外筒の内周面と薄肉内筒部の外周面の間に形成されると
ともに封入された作動流体で該薄肉内筒部の外周面に締
付力を与える液圧室と、 液圧室内に回動自在に収容配置された複数の締付片とを
備え、 前記締付片は、外筒の内周面に当接した外側当接部と、
薄肉内筒部の外周面に当接した内側当接部とを有し、締
付片の重心は、該締付片において外側当接部とチャック
本体の軸心を結ぶ線よりも内側当接部の反対側に位置し
ていることを特徴とする液圧チャック。1. A chuck body having a base end mounted on a main shaft of a machine tool, an outer cylinder formed on a distal end side of the chuck body, and a thin inner wall disposed inside the outer cylinder and holding a tool on an inner peripheral surface. A cylinder portion, a hydraulic chamber formed between the inner peripheral surface of the outer cylinder and the outer peripheral surface of the thin inner cylinder portion and applying a clamping force to the outer peripheral surface of the thin inner cylinder portion with a sealed working fluid; A plurality of tightening pieces rotatably housed and arranged in the hydraulic chamber, wherein the tightening pieces have an outer contact portion abutting on the inner peripheral surface of the outer cylinder,
An inner abutting portion abutting on the outer peripheral surface of the thin inner cylindrical portion, wherein the center of gravity of the fastening piece is inwardly abutting more than a line connecting the outer abutting portion and the axis of the chuck body in the fastening piece. A hydraulic chuck, which is located on the opposite side of the part.
ャック本体と、 チャック本体の先端側に形成された外筒と、 外筒の内側に配置され工具を内周面で把持する薄肉内筒
部と、 外筒の内周面と薄肉内筒部の外周面の間に形成されると
ともに封入された作動流体で該薄肉内筒部の外周面に締
付力を与える液圧室と、 液圧室内に回動自在に収容配置された複数の締付片とを
備え、 前記締付片は、外筒の内周面に当接自在の外側当接部
と、薄肉内筒部の外周面に当接自在の内側当接部とを有
し、締付片の重心は、該締付片において外側当接部とチ
ャック本体の軸心を結ぶ線よりも内側当接部の反対側に
位置していることを特徴とする液圧チャック。2. A chuck body having a base end mounted on a main shaft of a machine tool, an outer cylinder formed on a distal end side of the chuck body, and a thin inner wall disposed inside the outer cylinder and holding a tool on an inner peripheral surface. A cylinder portion, a hydraulic chamber formed between the inner peripheral surface of the outer cylinder and the outer peripheral surface of the thin inner cylinder portion and applying a clamping force to the outer peripheral surface of the thin inner cylinder portion with a sealed working fluid; A plurality of tightening pieces rotatably housed and arranged in the hydraulic chamber, wherein the tightening pieces are capable of abutting on the inner peripheral surface of the outer cylinder and an outer peripheral portion of the thin inner cylindrical section. The surface has an inner contact portion that can be freely contacted, and the center of gravity of the fastening piece is on the opposite side of the inner contact portion from the line connecting the outer contact portion and the axis of the chuck body in the fastening piece. A hydraulic chuck characterized by being located.
る薄肉外筒と、 薄肉外筒の内側に配置されて環状溝を有する軸部と、 薄肉外筒の内周面と軸部の環状溝の間に形成されて封入
された作動流体で該薄肉外筒の内周面に締付力を与える
液圧室と、 液圧室内に回動自在に収容配置された複数の締付片とを
備え、 締付片は、薄肉外筒の内周面に当接した外側当接部と、
軸部の環状溝に当接した内側当接部とを有し、締付片の
重心は、該締付片において外側当接部とチャック本体の
軸心を結ぶ線よりも内側当接部の反対側に位置している
ことを特徴とする液圧チャック。3. A thin outer cylinder for gripping a hole of a cylindrical portion of a workpiece with an outer peripheral surface, a shaft portion disposed inside the thin outer cylinder and having an annular groove, and an inner peripheral surface and a shaft of the thin outer cylinder. A hydraulic chamber formed between the annular grooves of the section to apply a clamping force to the inner peripheral surface of the thin outer cylinder with a working fluid sealed therein; and a plurality of clamps rotatably housed and disposed in the hydraulic chamber. An outer contact portion abutting the inner peripheral surface of the thin outer cylinder;
An inner contact portion in contact with the annular groove of the shaft portion, and the center of gravity of the fastening piece is located on the inner contact portion with respect to a line connecting the outer contact portion and the axis of the chuck body in the fastening piece. A hydraulic chuck, which is located on the opposite side.
る薄肉外筒と、 薄肉外筒の内側に配置されて環状溝を有する軸部と、 薄肉外筒の内周面と軸部の環状溝の間に形成されて封入
された作動流体で該薄肉外筒の内周面に締付力を与える
液圧室と、 液圧室内に回動自在に収容配置された複数の締付片とを
備え、 締付片は、薄肉外筒の内周面に当接自在の外側当接部
と、軸部の環状溝に当接自在の内側当接部とを有し、締
付片の重心は、該締付片において外側当接部とチャック
本体の軸心を結ぶ線よりも内側当接部の反対側に位置し
ていることを特徴とする液圧チャック。4. A thin outer cylinder for gripping a hole of a cylindrical portion of a workpiece with an outer peripheral surface, a shaft portion disposed inside the thin outer cylinder and having an annular groove, and an inner peripheral surface and a shaft of the thin outer cylinder. A hydraulic chamber formed between the annular grooves of the section to apply a clamping force to the inner peripheral surface of the thin outer cylinder with a working fluid sealed therein; and a plurality of clamps rotatably housed and disposed in the hydraulic chamber. The fastening piece has an outer abutting portion that can abut on the inner peripheral surface of the thin outer cylinder and an inner abutting portion that can abut on the annular groove of the shaft portion. The hydraulic chuck according to claim 1, wherein a center of gravity of the piece is located on a side of the fastening piece opposite to an inner contact portion with respect to a line connecting the outer contact portion and the axis of the chuck body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01356294A JP3317419B2 (en) | 1994-02-07 | 1994-02-07 | Hydraulic chuck |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01356294A JP3317419B2 (en) | 1994-02-07 | 1994-02-07 | Hydraulic chuck |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07223103A JPH07223103A (en) | 1995-08-22 |
| JP3317419B2 true JP3317419B2 (en) | 2002-08-26 |
Family
ID=11836619
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01356294A Expired - Lifetime JP3317419B2 (en) | 1994-02-07 | 1994-02-07 | Hydraulic chuck |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3317419B2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9901718D0 (en) * | 1999-01-26 | 1999-03-17 | Westwind Air Bearings Ltd | High speed drill holders |
| JP3998958B2 (en) * | 2001-12-11 | 2007-10-31 | 東芝機械株式会社 | Tool holder |
| GB0411686D0 (en) * | 2004-05-25 | 2004-06-30 | Westwind Air Bearing Ltd | Hydraulic chucks |
| DE502004002580D1 (en) * | 2004-12-13 | 2007-02-15 | Schunk Gmbh & Co Kg | tensioning device |
| JP5386256B2 (en) * | 2008-09-29 | 2014-01-15 | 日立ビアメカニクス株式会社 | Chuck |
| JP6561737B2 (en) * | 2015-09-30 | 2019-08-21 | 豊和工業株式会社 | Chuck |
-
1994
- 1994-02-07 JP JP01356294A patent/JP3317419B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07223103A (en) | 1995-08-22 |
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