JPH11320455A - Rotation speed regulating device for air rotation tool - Google Patents
Rotation speed regulating device for air rotation toolInfo
- Publication number
- JPH11320455A JPH11320455A JP10214162A JP21416298A JPH11320455A JP H11320455 A JPH11320455 A JP H11320455A JP 10214162 A JP10214162 A JP 10214162A JP 21416298 A JP21416298 A JP 21416298A JP H11320455 A JPH11320455 A JP H11320455A
- Authority
- JP
- Japan
- Prior art keywords
- speed adjusting
- air
- adjusting member
- speed
- rotation
- 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.)
- Granted
Links
Landscapes
- Portable Power Tools In General (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、空気回転工具にお
いて最大回転数をある程度以上にならないように制御す
るようにした空気回転工具の回転速度調節装置に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the rotation speed of a pneumatic rotary tool so that the maximum number of rotations of the pneumatic rotary tool does not exceed a certain value.
【０００２】[0002]
【従来の技術】エアグラインダーやエアサンダー等の空
気回転工具は、砥石等の回転研削物あるいは回転研磨物
等の加工工具を回転させて被研磨物等を研磨するもので
ある。加工工具は低速よりも高速の方が研削性や研磨性
が良く、しかも作業性も優れている。空気回転工具では
一般に、使用する圧力（常用圧力）が取扱説明書等で指
示されている。しかし、使用する圧力の指示が無視され
て、はるかに高い圧力で使用されているのが実情であ
る。図７に示すように、空気圧力を上げてゆけば、加工
工具の回転数は、一点鎖線（ａ）のように許容回転数を
越えるようになる。2. Description of the Related Art An air rotary tool such as an air grinder or an air sander is a tool for rotating a grinding tool such as a grindstone or a processing tool such as a rotary abrasive to grind an object to be polished. A high-speed machining tool has better grinding and polishing properties than a low-speed machining tool, and has excellent workability. In the case of a pneumatic rotary tool, the pressure to be used (normal pressure) is generally specified in an instruction manual or the like. However, the fact that the indication of the pressure to be used is ignored is being used at a much higher pressure. As shown in FIG. 7, as the air pressure is increased, the rotational speed of the working tool exceeds the allowable rotational speed as shown by the dashed line (a).
【０００３】[0003]
【発明が解決しようとする課題】空気回転工具が許容回
転数を越えると、加工工具に強度以上の回転力（遠心
力）が働いて加工工具が破壊するおそれがある。加工工
具が破壊すると、破壊物が四方に飛散して作業者や周囲
の人にが怪我をするおそれがあり、極めて危険である。
この点から、エアグラインダーやエアサンダー等の空気
回転工具では、回転数を最大許容回転数以下に押える必
要があった。即ち、図７の実線（ｂ）のように許容回転
数を越えないものが望ましい。また、空気回転工具が許
容回転数を越えないように維持するために、自動的に空
気供給量を調節して、モータ回転数が所定の回転数の範
囲内で増加と減少とを繰り返そうとする。このモータ回
転数の増加或は減少との繰り返し動作において回転速度
調節装置の速度調節部材が軸方向に伸縮振動を起こすと
いう欠点があった。If the rotational speed of the air-rotated tool exceeds the permissible rotational speed, a rotational force (centrifugal force) higher than the strength acts on the processing tool, and the processing tool may be broken. When the processing tool is destroyed, the broken object scatters in all directions, which may injure the worker and the surrounding people, which is extremely dangerous.
From this point, in the case of an air rotating tool such as an air grinder or an air sander, it is necessary to keep the number of revolutions below the maximum allowable number of revolutions. That is, it is desirable that the rotation speed does not exceed the allowable rotation speed as shown by the solid line (b) in FIG. Also, in order to keep the air rotating tool from exceeding the allowable rotation speed, the air supply amount is automatically adjusted so that the motor rotation speed repeatedly increases and decreases within a predetermined rotation speed range. . There is a drawback that the speed adjusting member of the rotation speed adjusting device causes expansion and contraction vibration in the axial direction in the repeated operation of increasing or decreasing the motor rotation speed.
【０００４】本発明は上記の点に鑑みてなされたもの
で、高い空気圧力が供給されても最大許容回転数を越え
ないようにして加工工具の破損を生じないようにした空
気回転工具の回転速度調節装置を提供することを目的と
するものである。本発明はまた、振動による回転ムラの
生じることのない空気回転工具の回転速度調節装置を提
供することを目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made in consideration of the above-described problems. It is an object to provide a speed adjusting device. Another object of the present invention is to provide an apparatus for adjusting the rotation speed of an air rotary tool, which does not cause rotation unevenness due to vibration.
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するため
に本発明の空気回転工具の回転速度調節装置は、内部に
空気導入通路を形成したメインボディと、その空気導入
通路から供給される空気によって回転発生手段と、その
回転力発生手段の構成部材としてのロータとを有する空
気回転工具において、前記メインボディに通路断面の狭
いベンチュリー部を形成し、前記ロータの一端に速度調
節用シャフトを固定し、この速度調節用シャフトに対し
て変位可能な速度調節用部材を備え、前記速度調節用シ
ャフトの回転中心軸に対する半径方向に移動可能で速度
調節用部材にボールを備え、そのボールにかかる遠心力
で速度調節用部材を前記速度調節用シャフトの回転中心
軸の軸方向に対して変位させ、前記ロータの回転数が許
容回転数近辺に達した場合の速度調節用部材の変位位置
で前記速度調節用部材の先端と前記ベンチュリー部との
間の空気導入通路の断面を狭くして前記ロータの回転数
が許容回転数を越えない供給空気量とするようにしたも
のである。本発明は更に、前記速度調節用部材が一端閉
鎖の筒状形状とし、その速度調節用部材の変位によって
一端閉鎖の筒状の速度調節用部材と速度調節用シャフト
の先端との間に空間を形成するようにし、前記突出部に
その空間と前記空気導入通路とを連絡する貫通小孔を形
成し減衰効果を持たせるようにしたものである。SUMMARY OF THE INVENTION In order to achieve the above object, a rotation speed adjusting device for an air rotary tool according to the present invention comprises a main body having an air introduction passage formed therein, and air supplied from the air introduction passage. In a pneumatic rotating tool having a rotation generating means and a rotor as a component of the rotating force generating means, a Venturi portion having a narrow passage cross section is formed in the main body, and a speed adjusting shaft is fixed to one end of the rotor. A speed adjusting member displaceable with respect to the speed adjusting shaft; a ball capable of moving in a radial direction with respect to a rotation center axis of the speed adjusting shaft; The speed adjusting member is displaced with respect to the axial direction of the rotation center axis of the speed adjusting shaft by force, and the rotation speed of the rotor reaches around the allowable rotation speed. In the case where the speed adjustment member is displaced, the cross section of the air introduction passage between the tip of the speed adjustment member and the venturi portion is narrowed at the displacement position of the speed adjustment member so that the amount of supply air such that the rotation speed of the rotor does not exceed the allowable rotation speed It is intended to be. According to the present invention, further, the speed adjusting member has a cylindrical shape with one end closed, and the space between the cylindrical speed adjusting member with one end closed and the tip of the speed adjusting shaft is formed by displacement of the speed adjusting member. The projecting portion is formed with a small through hole communicating the space and the air introduction passage so as to have a damping effect.
【０００６】[0006]
【発明の実施の形態】次に本発明を図面に基づいて説明
する。図１は本発明に係る回転速度調節装置を備えた空
気回転工具の全体断面図、図２は図１の要部拡大縦断面
図である。図３は図２の要部拡大縦断面図である。空気
回転工具は、メインボディ１０と、その内部に加圧空気
を導入するために形成された空気導入通路１２と、その
空気導入通路１２からの供給空気によって回転力を発生
させるための回転力発生手段１４とを有している。この
空気回転工具に、砥石等の回転研削物や回転研磨物等の
加工工具１６が着脱自在に取り付けられる。回転力発生
手段１４は、ハウジングとなるシリンダ１８とフロント
プレート２０とリアプレート２２を有し、そのハウジン
グの内部に空間２４を形成し、その空間２４の内部にロ
ータ２６とそのロータ２６に半径方向に出入りする複数
のベーン２８とを備えたものである。回転力発生手段１
４の空間２４内に空気導入通路１２からの空気が供給さ
れ、その供給空気がベーン２８に当たってロータ２６を
回転させ、それによって加工工具１６を回転させる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is an overall sectional view of a pneumatic rotary tool provided with a rotation speed adjusting device according to the present invention, and FIG. 2 is an enlarged vertical sectional view of a main part of FIG. FIG. 3 is an enlarged vertical sectional view of a main part of FIG. The air rotating tool includes a main body 10, an air introduction passage 12 formed to introduce pressurized air into the main body 10, and a rotational force generation for generating a rotational force by air supplied from the air introduction passage 12. Means 14. A processing tool 16 such as a rotary grinding product such as a grindstone or a rotary polishing product is detachably attached to the air rotary tool. The rotating force generating means 14 has a cylinder 18 serving as a housing, a front plate 20 and a rear plate 22, forms a space 24 inside the housing, and has a rotor 26 and a radial direction And a plurality of vanes 28 entering and exiting the vehicle. Torque generating means 1
The air from the air introduction passage 12 is supplied into the space 24 of the fourth, and the supplied air impinges on the vane 28 to rotate the rotor 26, thereby rotating the processing tool 16.
【０００７】図２に示すように、ロータ２６のリアプレ
ート２２側の自由端に、速度調節用シャフト３０が回転
中心軸を同一にして固定される。この速度調節用シャフ
ト３０は前記空気導入通路１２内に位置している。速度
調節用シャフト３０の外側には、キャップ状の速度調節
用部材３２が被せられており、速度調節用部材３２の筒
状の内壁は速度調節用シャフト３０の外壁に摺接しなが
ら移動するように設定されている。この速度調節用部材
３２の筒状の側面には、軸方向に一対の穴３４が形成さ
れる。速度調節用シャフト３０には、軸方向と直角方向
に速度調節用シャフト３０と速度調節用部材３２の穴３
４を貫通するピン３６が固定され、そのピン３６の両端
は速度調節用部材３２の穴３４の外側に突出している。
速度調節用部材３２の穴３４の外側に突出しているピン
３６の両端には、カバー３８が被せられて、そのカバー
３８と速度調節用部材３２のリアプレート２２側との間
にスプリング４０が備えられる。このスプリング４０
は、速度調節用部材３２を常にロータ２６側に向けて付
勢するためのものである。As shown in FIG. 2, a speed adjusting shaft 30 is fixed to the free end of the rotor 26 on the rear plate 22 side with the same rotation center axis. The speed adjusting shaft 30 is located in the air introduction passage 12. A cap-shaped speed adjusting member 32 is covered on the outside of the speed adjusting shaft 30 so that the cylindrical inner wall of the speed adjusting member 32 moves while slidingly contacting the outer wall of the speed adjusting shaft 30. Is set. A pair of holes 34 is formed in the cylindrical side surface of the speed adjusting member 32 in the axial direction. The shaft 30 for speed adjustment and the hole 3 of the member 32 for speed adjustment
4 is fixed, and both ends of the pin 36 project outside the hole 34 of the speed adjusting member 32.
Both ends of the pin 36 projecting outside the hole 34 of the speed adjusting member 32 are covered with covers 38, and a spring 40 is provided between the cover 38 and the rear plate 22 side of the speed adjusting member 32. Can be This spring 40
Is for always urging the speed adjusting member 32 toward the rotor 26 side.
【０００８】前記速度調節用シャフト３０には、軸中心
に対して直角な面に、外表面から軸中心に向けてやや内
側に伸びる複数個の孔４２が形成され、各孔４２にはボ
ール４４が備えられる。前記キャップ状の速度調節用部
材３２の筒状の端付近の内壁は、軸方向から外側に向け
て徐々に開く形状の傾斜壁４６となっている。前記ボー
ル４４はこの傾斜壁４６に接触している。メインボディ
１０の内部に形成される空気導入通路１２の途中には、
図３に示すようにベンチュリー部４８が形成され、その
ベンチュリー部４８の直径をＤとする。The speed adjusting shaft 30 is formed with a plurality of holes 42 extending slightly inward from the outer surface toward the axis center on a plane perpendicular to the axis center. Is provided. The inner wall near the cylindrical end of the cap-shaped speed adjusting member 32 is an inclined wall 46 that gradually opens outward from the axial direction. The ball 44 is in contact with the inclined wall 46. In the middle of the air introduction passage 12 formed inside the main body 10,
As shown in FIG. 3, a venturi portion 48 is formed, and the diameter of the venturi portion 48 is D.
【０００９】キャップ状の速度調節用部材３２は、図３
に示すように、速度調節用シャフト３０の外側の筒状部
５０と、先端閉鎖部５２と、その先端閉鎖部５２に形成
されるもので前記筒状部５０より直径が小さい突出部５
４とからなる。更に、この突出部５４の先端付近には、
先端に近づくにつれて先細となるテーパ部５６を形成す
る。この突出部５４の径大部の直径をｄとすると、この
直径ｄはベンチュリー部４８の直径Ｄより小さいものに
設定する。なお、キャップ状の速度調節用部材３２にお
いては、図３に示すように、テーパ状の突出部５４の根
元の外径を前記筒状部５０の外径をより小さいものとし
たが、テーパ状の突出部５４の根元の外径を筒状部５０
の外径と同一にするようにしても良い。また、テーパ状
をストレート状にしても良い。突出部５４には、そこを
貫通して前記筒状部５０の内部に通じる貫通小孔５８が
形成されている。先端閉鎖部５２に突出部５４が形成さ
れていない場合には、先端閉鎖部５２に内部に通じる貫
通小孔５８を形成するようにしても良い。The cap-shaped speed adjusting member 32 is shown in FIG.
As shown in FIG. 5, a cylindrical portion 50 outside the speed adjusting shaft 30, a distal end closing portion 52, and a projecting portion 5 formed on the distal end closing portion 52 and having a smaller diameter than the cylindrical portion 50.
4 Further, in the vicinity of the tip of the protruding portion 54,
A tapered portion 56 that tapers toward the tip is formed. Assuming that the diameter of the large diameter portion of the projecting portion 54 is d, the diameter d is set to be smaller than the diameter D of the venturi portion 48. In the cap-shaped speed adjusting member 32, as shown in FIG. 3, the outer diameter of the base of the tapered protrusion 54 is smaller than the outer diameter of the cylindrical part 50. The outer diameter of the base of the projecting portion 54 is
May be made the same as the outer diameter of. Further, the tapered shape may be a straight shape. The projecting portion 54 is formed with a small through hole 58 penetrating therethrough and communicating with the inside of the tubular portion 50. In the case where the protruding portion 54 is not formed in the distal end closing portion 52, a small through hole 58 communicating with the inside may be formed in the distal end closing portion 52.
【００１０】次に、動作について説明する。空気導入通
路１２からの加圧空気の供給空気量が多くなると、回転
力発生手段１４のロータ２６の回転数が上昇し、ロータ
２６に固定されている速度調節用シャフト３０の回転数
も上昇する。速度調節用シャフト３０の回転数が増大す
ると、その孔４２に収容されているボール４４に遠心力
が与えられる。速度調節用シャフト３０の回転数の増加
に応じてボール４４が傾斜壁４６を押す力が大きくな
り、図２並びに図３で速度調節用部材３２を右方向に移
動させる。即ち、速度調節用シャフト３０の回転数の増
加に応じて、速度調節用部材３２を図２並びに図３で右
方向に移動する。速度調節用シャフト３０の回転数が所
定以上になると、速度調節用部材３２の突出部５４がベ
ンチュリー部４８に突入し、図３及び図４に示すように
ベンチュリー部４８における空気導入通路１２の通路断
面が狭くなり、空気導入通路１２から回転力発生手段１
４への供給空気量が制限される。この結果、図５に示す
ように、速度調節用シャフト３０の回転数は最大許容回
転数を大きく越えることがない。Next, the operation will be described. As the amount of pressurized air supplied from the air introduction passage 12 increases, the rotational speed of the rotor 26 of the rotational force generating means 14 increases, and the rotational speed of the speed adjusting shaft 30 fixed to the rotor 26 also increases. . When the rotational speed of the speed adjusting shaft 30 increases, a centrifugal force is applied to the ball 44 housed in the hole 42. As the rotational speed of the speed adjusting shaft 30 increases, the force by which the ball 44 pushes the inclined wall 46 increases, and moves the speed adjusting member 32 rightward in FIGS. 2 and 3. That is, the speed adjusting member 32 is moved rightward in FIGS. 2 and 3 in accordance with an increase in the rotation speed of the speed adjusting shaft 30. When the rotation speed of the speed adjusting shaft 30 becomes equal to or higher than a predetermined value, the protrusion 54 of the speed adjusting member 32 protrudes into the venturi portion 48, and as shown in FIGS. 3 and 4, the passage of the air introduction passage 12 in the venturi portion 48. The cross section becomes narrower, and the rotational force generating means 1
4 is limited. As a result, as shown in FIG. 5, the rotation speed of the speed adjusting shaft 30 does not greatly exceed the maximum allowable rotation speed.
【００１１】突出部５４の先端付近に先細となるテーパ
部５６を付けることによって、空気の流れがスムースに
なり、応答性や安定性が良い。なお、図１乃至図３にお
いては、突出部５４の先端付近のみにテーパ部５６を設
けたが、図６に示すように、突出部５４の軸方向の全長
にわたって先細となるテーパ部６０を形成しても良い。
なお、突出部５４を円柱形状にしても良い。図４に示す
ように、ベンチュリー部４８におけるメインボディ１０
と突出部５４との隙間Ｓは、突出部５４を一段細くした
ことにより大きくすることができるので、空気回転工具
の振動等により突出部５４が若干振れても、ベンチュリ
ー部４８におけるメインボディ１０と突出部５４とが接
触することはなく、速度調節用部材３２の摺動性に影響
は無い。By providing a tapered portion 56 near the tip of the protruding portion 54, the flow of air becomes smooth, and responsiveness and stability are good. In FIGS. 1 to 3, the tapered portion 56 is provided only near the tip of the projecting portion 54, but as shown in FIG. 6, a tapered portion 60 tapering over the entire length of the projecting portion 54 in the axial direction is formed. You may.
Note that the protruding portion 54 may have a cylindrical shape. As shown in FIG. 4, the main body 10 in the venturi section 48
The gap S between the protruding portion 54 and the protruding portion 54 can be increased by making the protruding portion 54 one step narrower. There is no contact between the protrusion 54 and the slidability of the speed adjusting member 32.
【００１２】図３に示すように、速度調節用シャフト３
０に対して速度調節用部材３２が離れる方向に変位する
と、速度調節用部材３２の先端閉鎖部５２と速度調節用
シャフト３０の先端面との間に空間６２が形成される。
速度調節用シャフト３０の先端閉鎖部５２の突出部５４
に形成される貫通小孔５８は、一方を空間６２と連絡
し、他方を前記空気導入通路１２と連絡する。もし、速
度調節用部材３２に空間６２に至る貫通小孔５８が形成
されないとすると、空間６２の容積が大きくなるとその
空間６２内に大きな負圧が発生し、速度調節用部材３２
の応答性や安定性が悪くなる。このため、速度調節用部
材３２に空間６２と空気導入通路１２とを連絡する貫通
小孔５８を形成することによって、貫通小孔５８からこ
の空間６２に空気が出入りして、速度調節用部材３２の
移動をスムースに行わせることができる。As shown in FIG. 3, the speed adjusting shaft 3
When the speed adjusting member 32 is displaced away from 0, a space 62 is formed between the distal end closing portion 52 of the speed adjusting member 32 and the distal end surface of the speed adjusting shaft 30.
Projection 54 of tip closure 52 of speed adjustment shaft 30
One of the small through holes 58 is connected to the space 62 and the other is connected to the air introduction passage 12. If the small through-hole 58 reaching the space 62 is not formed in the speed adjusting member 32, a large negative pressure is generated in the space 62 when the volume of the space 62 increases, and the speed adjusting member 32
Responsiveness and stability are deteriorated. For this reason, by forming a small through hole 58 that connects the space 62 and the air introduction passage 12 to the speed adjusting member 32, air flows into and out of the space 62 through the small through hole 58, and the speed adjusting member 32 is formed. Can be smoothly performed.
【００１３】従来から、工具の回転速度調節装置におい
ては、モータ回転数の増加或は減少という繰り返し動作
が行われ、ロータに回転ムラが生じるという欠点があっ
た。本発明においては、遠心力を発生するボール４４の
重量や、スプリング４０の強さや、速度調節用シャフト
３０と速度調節用部材３２の摺動部分の摺動抵抗や、供
給空気の流量や圧力の具合によって、速度調節用部材３
２が速度調節用シャフト３０に対して軸方向に振動し、
その振動によって流入空気量が変化し、その流入空気量
の変化によってロータ２６に回転ムラが発生するおそれ
があった。Conventionally, the rotational speed adjusting device for a tool has a drawback in that a repetitive operation of increasing or decreasing the number of rotations of a motor is performed, and rotation irregularities occur in a rotor. In the present invention, the weight of the ball 44 generating the centrifugal force, the strength of the spring 40, the sliding resistance of the sliding portion between the speed adjusting shaft 30 and the speed adjusting member 32, the flow rate and pressure of the supply air, and the like. Depending on the condition, the speed adjusting member 3
2 vibrates in the axial direction with respect to the speed adjusting shaft 30,
The vibration changes the inflow air amount, and the change in the inflow air amount may cause uneven rotation of the rotor 26.
【００１４】しかし、空間６２と空気導入通路１２とを
連絡する貫通小孔５８を速度調節用部材３２に形成する
ことによって、この貫通小孔５８を出入りする空気の抵
抗が速度調節用シャフト３０に対する速度調節用部材３
２の軸方向の振動を解消する。即ち、回転力発生手段１
４の回転が上昇すると、空気導入通路１２から貫通小孔
５８を経て空間６２に移動する空気の流入抵抗が発生
し、この空気の流入抵抗が速度調節用部材３２に発生す
る軸方向の振動を防止し、ロータ２６の回転ムラを防止
する。また、回転力発生手段１４の回転が下降すると、
空間６２から貫通小孔５８を経て空気導入通路１２に移
動する空気の流出抵抗が発生し、この空気の流出抵抗が
速度調節用部材３２に発生する軸方向の振動を防止し、
ロータ２６の回転ムラを防止する。However, by forming the small through-hole 58 connecting the space 62 and the air introduction passage 12 in the speed adjusting member 32, the resistance of the air entering and exiting the small through-hole 58 to the speed adjusting shaft 30 is reduced. Speed adjustment member 3
2 eliminates vibration in the axial direction. That is, the torque generating means 1
When the rotation of 4 increases, an inflow resistance of the air moving from the air introduction passage 12 to the space 62 through the small through hole 58 is generated, and the inflow resistance of the air causes an axial vibration generated in the speed adjusting member 32. And uneven rotation of the rotor 26 is prevented. Also, when the rotation of the rotational force generating means 14 decreases,
The outflow resistance of the air moving from the space 62 to the air introduction passage 12 through the small through-hole 58 is generated, and the outflow resistance of the air prevents axial vibration generated in the speed adjusting member 32,
The rotation unevenness of the rotor 26 is prevented.
【００１５】前記貫通小孔５８の直径を０．５ｍｍ〜２
ｍｍ（上下の数値を含むものとする）にすれば、速度調
節用シャフト３０に対する速度調節用部材３２の軸方向
の振動をなくし、ロータ２６の回転ムラを解消すること
ができる。貫通小孔５８の直径を０．５ｍｍ〜２ｍｍ程
度の小さいものとすることによって、貫通小孔５８を通
過する空気の抵抗力を十分利用することができ、この空
気抵抗力によって回転速度調節装置の速度調節用部材３
２に発生する振動をなくし、ロータ２６の回転ムラを防
止することができる。貫通小孔５８の直径が０．５ｍｍ
より小さくなると、空気の抵抗力は大となるが、貫通小
孔５８の加工の難易さやゴミ等の目詰まり等を考慮する
と好ましくない。貫通小孔５８の直径が２ｍｍより大き
くなると、貫通小孔５８を通過する空気の抵抗力が弱く
なり、速度調節用部材３２の軸方向の振動を抑制する効
果が殆どなくなる。実際に使用される回転速度調節装置
では、空間６２の内径は５０ｍｍ以下であるので、この
間におけるどのような内径の空間６２に対しても、貫通
小孔５８の直径は０．５ｍｍ〜２ｍｍ（上下の数値を含
むものとする）の範囲で十分である。The diameter of the small through hole 58 is 0.5 mm to 2 mm.
mm (including the upper and lower numerical values), the vibration of the speed adjusting member 32 in the axial direction with respect to the speed adjusting shaft 30 can be eliminated, and the rotation unevenness of the rotor 26 can be eliminated. By making the diameter of the small through-hole 58 as small as about 0.5 mm to 2 mm, the resistance of the air passing through the small through-hole 58 can be sufficiently utilized. Speed adjustment member 3
2 can be eliminated, and rotation unevenness of the rotor 26 can be prevented. The diameter of the through hole 58 is 0.5 mm
If the diameter is smaller, the resistance of the air becomes larger, but it is not preferable in view of the difficulty of processing the small through hole 58 and clogging of dust and the like. If the diameter of the small through hole 58 is larger than 2 mm, the resistance of the air passing through the small through hole 58 becomes weak, and the effect of suppressing the axial vibration of the speed adjusting member 32 is almost eliminated. In the rotation speed adjusting device actually used, the inside diameter of the space 62 is 50 mm or less, so that the diameter of the small through hole 58 is 0.5 mm to 2 mm (up and down) for the space 62 having any inside diameter in the meantime. ) Is sufficient.
【００１６】[0016]
【発明の効果】以上のように、本発明に係わる空気回転
工具の回転速度調節装置によれば、ロータの回転数が所
定以上に達すると、ロータに固定される速度調節用シャ
フトに対して軸方向に移動する速度調節用部材によっ
て、空気導入通路から回転力発生手段への供給空気量を
制限する。このように、ロータの回転数が所定の値に達
すると空気導入通路からの供給空気量を制限するので、
ロータの回転数を最大許容回転数を越えなくすることが
でき、この結果、回転研削物や回転研磨物等の加工工具
の破損を防止することができる。また、速度調節用シャ
フトと速度調節用部材との間に形成される空間と空気導
入通路との間に、それら空間と空気導入通路とを連絡す
る貫通小孔を形成することによって、その貫通小孔を通
過する空気の抵抗力によって、速度調節用部材に発生す
る軸方向の振動を防いで、ロータの回転ムラを防止して
安定的な回転を行うことができる。更に、速度調節用部
材の先端突出部にテーパ部を設けることによって、空気
の流れがスムースになり、応答性や安定性を良くするこ
とができる。As described above, according to the apparatus for adjusting the rotation speed of a pneumatic rotating tool according to the present invention, when the rotation speed of the rotor reaches a predetermined value or more, the shaft is adjusted with respect to the speed adjustment shaft fixed to the rotor. The amount of air supplied from the air introduction passage to the torque generating means is limited by the speed adjusting member moving in the direction. As described above, when the rotation speed of the rotor reaches a predetermined value, the amount of air supplied from the air introduction passage is limited.
The number of rotations of the rotor can be made not to exceed the maximum allowable number of rotations, and as a result, it is possible to prevent breakage of a processing tool such as a rotary grinding product or a rotary polishing product. Further, by forming a small through hole communicating between the space and the air introduction passage between the space formed between the speed adjusting shaft and the speed adjusting member and the air introduction passage, the small through hole is formed. The resistance of the air passing through the hole prevents the vibration in the axial direction generated in the speed adjusting member, thereby preventing the rotor from rotating unevenly and performing stable rotation. Further, by providing the tapered portion at the tip end protruding portion of the speed adjusting member, the air flow becomes smooth, and the responsiveness and stability can be improved.
【図１】本発明に係る回転速度調節装置を備えた空気回
転工具の全体断面図である。FIG. 1 is an overall sectional view of a pneumatic rotary tool provided with a rotation speed adjusting device according to the present invention.
【図２】図１の要部拡大縦断面図である。FIG. 2 is an enlarged vertical sectional view of a main part of FIG.
【図３】図２の要部拡大縦断面図である。FIG. 3 is an enlarged vertical sectional view of a main part of FIG. 2;
【図４】ベンチュリー部におけるメインボディと速度調
節用部材の要部断面図である。FIG. 4 is a sectional view of a main part of a main body and a speed adjusting member in a venturi section.
【図５】本発明に係る回転速度調節装置を備えた空気回
転工具の回転数と時間の特性図である。FIG. 5 is a characteristic diagram of rotation speed and time of an air rotary tool provided with a rotation speed adjusting device according to the present invention.
【図６】速度調節用部材の他の形状を示す部分断面図で
ある。FIG. 6 is a partial sectional view showing another shape of the speed adjusting member.
【図７】従来の空気回転工具の回転数と圧力の特性図で
ある。FIG. 7 is a characteristic diagram of a rotation speed and a pressure of a conventional pneumatic rotary tool.
【符合の説明】 １０ メインボディ １２ 空気導入通路 １４ 回転力発生手段 １６ 加工工具 ２６ ロータ ３０ 速度調節用シャフト ３２ 速度調節用部材 ３４ 穴 ４０ スプリング ４４ ボール ４６ 傾斜壁 ４８ ベンチュリー部 ５０ 筒状部 ５２ 先端閉鎖部 ５４ 突出部 ５６ テーパ部 ５８ 貫通小孔 ６０ テーパ部 ６２ 空間DESCRIPTION OF THE SYMBOLS 10 Main body 12 Air introduction passage 14 Rotating force generating means 16 Processing tool 26 Rotor 30 Speed adjusting shaft 32 Speed adjusting member 34 Hole 40 Spring 44 Ball 46 Inclined wall 48 Venturi part 50 Cylindrical part 52 Tip Closing portion 54 Projecting portion 56 Taper portion 58 Small through hole 60 Taper portion 62 Space
Claims (6)
ディと、その空気導入通路から供給される空気によって
回転発生手段と、その回転力発生手段の構成部材として
のロータとを有する空気回転工具において、前記メイン
ボディに通路断面の狭いベンチュリー部を形成し、前記
ロータの一端に速度調節用シャフトを固定し、この速度
調節用シャフトに対して変位可能な速度調節用部材を備
え、前記速度調節用シャフトの回転中心軸に対する半径
方向に移動可能で速度調節用部材にボールを備え、その
ボールにかかる遠心力で速度調節用部材を前記速度調節
用シャフトの回転中心軸の軸方向に対して変位させ、前
記ロータの回転数が許容回転数近辺に達した場合の速度
調節用部材の変位位置で前記速度調節用部材の先端と前
記ベンチュリー部との間の空気導入通路の断面を狭くし
て前記ロータの回転数が許容回転数を越えない供給空気
量とするようにしたことを特徴とする空気回転工具の回
転速度調節装置。1. An air rotating tool having a main body having an air introduction passage formed therein, a rotation generating means by air supplied from the air introduction passage, and a rotor as a component of the rotation force generating means. Forming a Venturi portion having a narrow passage cross section in the main body, fixing a speed adjusting shaft to one end of the rotor, and displacing a speed adjusting member with respect to the speed adjusting shaft; A ball is provided on the speed adjusting member movable in the radial direction with respect to the rotation center axis of the shaft, and the speed adjusting member is displaced in the axial direction of the rotation center axis of the speed adjustment shaft by centrifugal force applied to the ball. The tip of the speed adjusting member and the venturi portion at the displacement position of the speed adjusting member when the rotation speed of the rotor reaches around the allowable rotation speed. Wherein the cross section of the air introduction passage is narrowed so that the amount of supplied air does not exceed the permissible number of revolutions of the rotor.
状とし、その速度調節用部材の変位によって一端閉鎖の
筒状の速度調節用部材と速度調節用シャフトの先端との
間に空間を形成するようにし、前記突出部にその空間と
前記空気導入通路とを連絡する貫通小孔を形成したこと
を特徴とする請求項１項記載の空気回転工具の回転速度
調節装置。2. The speed adjusting member has a cylindrical shape with one end closed, and the space between the cylindrical speed adjusting member with one end closed and the tip of the speed adjusting shaft is formed by displacement of the speed adjusting member. 2. The apparatus according to claim 1, wherein said projecting portion is formed with a small through-hole communicating said space and said air introduction passage.
ｍとしたことを特徴とする請求項２記載の空気回転工具
の回転速度調節装置。3. The diameter of the small through hole is 0.5 mm to 2 m.
The rotational speed adjusting device for an air rotary tool according to claim 2, wherein m is set to m.
する面を、その速度調節用部材の移動方向に対して傾斜
した傾斜面とすることを特徴とする請求項１乃至３記載
の空気回転工具の回転速度調節装置。4. The air rotation according to claim 1, wherein a surface of the speed adjusting member that contacts the ball is an inclined surface that is inclined with respect to a moving direction of the speed adjusting member. Tool speed adjustment device.
節用シャフトから遠い位置に突出部を形成し、その突出
部に前記貫通小孔を形成し、その突出部と前記ベンチュ
リー部とで空気導入通路の狭い断面を形成することを特
徴とする請求項１乃至４記載の空気回転工具の回転速度
調節装置。5. A protruding portion is formed on the speed adjusting member at a position far from the speed adjusting shaft, the through hole is formed on the protruding portion, and an air introducing passage is formed between the protruding portion and the venturi portion. The rotation speed adjusting device for an air-rotated tool according to claim 1, wherein a narrow cross section is formed.
方向全体に、先端に向けて先細りとなるテーパ部を形成
したことを特徴とする請求項５記載の空気回転工具の回
転速度調節装置。6. The rotation speed adjusting device for an air-powered rotary tool according to claim 5, wherein a tapered portion tapering toward the distal end is formed near the distal end of the projecting portion or in the entire axial direction.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21416298A JP4364323B2 (en) | 1998-03-16 | 1998-07-29 | Rotational speed adjustment device for pneumatic tool |
| US09/312,820 US6066033A (en) | 1998-07-29 | 1999-05-17 | Rotational speed adjusting device for a pneumatic rotational tool |
| DE19928987A DE19928987A1 (en) | 1998-07-29 | 1999-06-24 | Revolution number regulation unit for air rotation tool such as air grinder, air sanding machine |
| FR9908291A FR2781898B1 (en) | 1998-07-29 | 1999-06-29 | ROTATION SPEED ADJUSTMENT DEVICE FOR PNEUMATIC ROTARY TOOL |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10-65026 | 1998-03-16 | ||
| JP6502698 | 1998-03-16 | ||
| JP21416298A JP4364323B2 (en) | 1998-03-16 | 1998-07-29 | Rotational speed adjustment device for pneumatic tool |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH11320455A true JPH11320455A (en) | 1999-11-24 |
| JP4364323B2 JP4364323B2 (en) | 2009-11-18 |
Family
ID=26406169
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21416298A Expired - Fee Related JP4364323B2 (en) | 1998-03-16 | 1998-07-29 | Rotational speed adjustment device for pneumatic tool |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4364323B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011508136A (en) * | 2007-12-20 | 2011-03-10 | アトラス・コプコ・ツールス・アクチボラグ | Gas driven rotary motor, tool provided with gas driven rotary motor, and method for adjusting rotational speed of gas driven rotary motor |
| JP2013144340A (en) * | 2012-01-16 | 2013-07-25 | Makita Corp | Electric power tool |
| US9724814B2 (en) | 2012-01-26 | 2017-08-08 | Makita Corporation | Impact tool |
| WO2019097733A1 (en) * | 2017-11-20 | 2019-05-23 | ヨコタ工業株式会社 | Speed governor for air motor, and air tool |
| CN117117391A (en) * | 2023-10-20 | 2023-11-24 | 珠海科创储能科技有限公司 | Flow rate adjusting device and flow rate adjusting method |
-
1998
- 1998-07-29 JP JP21416298A patent/JP4364323B2/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011508136A (en) * | 2007-12-20 | 2011-03-10 | アトラス・コプコ・ツールス・アクチボラグ | Gas driven rotary motor, tool provided with gas driven rotary motor, and method for adjusting rotational speed of gas driven rotary motor |
| JP2013144340A (en) * | 2012-01-16 | 2013-07-25 | Makita Corp | Electric power tool |
| WO2013108556A1 (en) * | 2012-01-16 | 2013-07-25 | 株式会社マキタ | Electric tool |
| US9724814B2 (en) | 2012-01-26 | 2017-08-08 | Makita Corporation | Impact tool |
| WO2019097733A1 (en) * | 2017-11-20 | 2019-05-23 | ヨコタ工業株式会社 | Speed governor for air motor, and air tool |
| CN117117391A (en) * | 2023-10-20 | 2023-11-24 | 珠海科创储能科技有限公司 | Flow rate adjusting device and flow rate adjusting method |
| CN117117391B (en) * | 2023-10-20 | 2024-01-26 | 珠海科创储能科技有限公司 | Flow rate adjusting device and flow rate adjusting method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4364323B2 (en) | 2009-11-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5496173A (en) | Dental handpiece having an automatically controlled turbine drive | |
| US5069620A (en) | Dental handpiece | |
| JP3640710B2 (en) | Dentistry turbine drive device with automatic rotational speed adjusting means | |
| JPS60257865A (en) | Spray chip | |
| JPH11320455A (en) | Rotation speed regulating device for air rotation tool | |
| JP7490252B2 (en) | Rotating jet nozzle assembly for pressure washer | |
| US6066033A (en) | Rotational speed adjusting device for a pneumatic rotational tool | |
| US8292569B2 (en) | Compressed air-motor for rotationally driven tools | |
| KR950004636Y1 (en) | Air motor | |
| US6554291B2 (en) | Housing and hub for an apparatus for securing a workpiece to a rotatable machine member | |
| JPH04226860A (en) | Apparatus for polishing outer peri- pheral surface contour of work- piece | |
| US4382638A (en) | Sealing structure of spindle device | |
| JP2857061B2 (en) | Spindle device using hydrodynamic bearing | |
| JP2001054846A (en) | Spherical surface working method and device thereof | |
| US6695573B2 (en) | Hand-held turbine power tool | |
| JP4804476B2 (en) | High torque dual chamber turbine rotor for handheld or spindle mounted air tools | |
| JPH0790443B2 (en) | Spindle device | |
| JPH04176538A (en) | Tool holder for machine tool | |
| US3526464A (en) | Pneumatic motor unit for machine tools | |
| US20060153721A1 (en) | Dual inlet rotary tool | |
| KR200243321Y1 (en) | Air sander | |
| JPH05337809A (en) | Vibration type polishing machine | |
| JPH04365568A (en) | Air motor | |
| JP2000300376A (en) | Length adjustable strut for chair or table and length adjusting element therefor | |
| JP2646540B2 (en) | Spindle device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050719 |
|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A711 Effective date: 20071205 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20071205 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080304 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080318 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080516 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20090623 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20090701 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090728 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090819 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120828 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |