JP5785929B2

JP5785929B2 - Dental handpiece

Info

Publication number: JP5785929B2
Application number: JP2012279364A
Authority: JP
Inventors: 孝彰則近
Original assignee: J Morita Manufaturing Corp
Current assignee: J Morita Manufaturing Corp
Priority date: 2012-12-21
Filing date: 2012-12-21
Publication date: 2015-09-30
Anticipated expiration: 2032-12-21
Also published as: JP2014121445A

Description

本発明は、歯科用ハンドピースに関し、具体的には、歯間の清掃等に使用される歯科用ハンドピースの改良に関するものである。 The present invention relates to a dental handpiece, and more specifically to an improvement of a dental handpiece used for cleaning between teeth or the like.

歯科用ハンドピースとして、ハンドピース本体部（把持部）に内蔵される軸回転駆動伝達部からの軸回転運動を、先端ヘッド部に装着される歯科用工具を、前記軸回転駆動伝達部の軸心に直交する方向の往復運動に変換するよう構成されたものがある（例えば、特許文献１及び２参照）。特許文献１には、把持部内の回転軸の先端に設けられた偏心軸を頭部筐体内の、根管治療用切削具を嵌合保持する作動駒の外周面に設けられた嵌合凹溝に嵌合させることによって、回転軸の軸回転を、前記作動駒の該回転軸に直交する方向への往復動に変換させるよう構成された歯科用ハンドピースが開示されている。また、特許文献２にも、ハンドピース内の駆動キャリッジの先端に設けられた偏心円筒駆動ピンを、角度ヘッド筐体に設けられる工具装着用の中空円筒ラムスリーブの外周に設けられる周辺溝に嵌合させることによって、前記駆動キャリッジの軸回転を、前記中空円筒ラムスリーブの該駆動キャリッジの軸に直交する方向への往復動に変換させるよう構成された歯科用ハンドピースが開示されている。 As a dental handpiece, the shaft rotation movement from the shaft rotation drive transmission unit built in the handpiece main body (gripping unit), the dental tool attached to the tip head unit, the shaft of the shaft rotation drive transmission unit Some are configured to convert to a reciprocating motion in a direction perpendicular to the center (for example, see Patent Documents 1 and 2). In Patent Document 1, an eccentric shaft provided at the tip of a rotating shaft in a gripping part is fitted into a fitting groove provided in an outer peripheral surface of a working piece for fitting and holding a root canal treatment cutting tool in a head housing. There is disclosed a dental handpiece configured to convert the shaft rotation of a rotating shaft into a reciprocating motion of the operating piece in a direction orthogonal to the rotating shaft by fitting. Also in Patent Document 2, an eccentric cylindrical drive pin provided at the tip of a drive carriage in a handpiece is fitted in a peripheral groove provided on the outer periphery of a hollow cylindrical ram sleeve for tool mounting provided in an angle head housing. In combination, a dental handpiece configured to convert shaft rotation of the drive carriage into reciprocation of the hollow cylindrical ram sleeve in a direction perpendicular to the axis of the drive carriage is disclosed.

実公平４−１１６９５号公報Japanese Utility Model Publication No. 4-11695 特許第１７８１１２５号公報Japanese Patent No. 1781125

ところで、前記両特許文献１，２における偏心軸及び偏心円筒駆動ピン（以下、これらを偏心軸と言う）は、嵌合凹溝及び周辺溝（以下、これらを凹溝と言う）に、その溝壁に直接接するように嵌合されている。そして、前記偏心軸の偏心回転に伴うカム作用によって、前記凹溝の溝壁をカムフォロアとして、前記作動駒及び中空円筒ラムスリーブを軸回転駆動伝達部としての前記回転軸及び駆動キャリッジの軸に直交する方向に往復動させるようにしている。即ち、カムとしての偏心軸が前記カムフォロアとしての溝壁に擦れ合いながら偏心回転するため、偏心軸の摩耗及び損傷が激しい。しかも、前記偏心軸の周面の全周が前記溝壁に擦れ合うが、前記回転軸及び駆動キャリッジの軸から遠い部分の回転半径が最も大きいため、この部分の前記擦れ合時の周速度が最も大きく、これによってこの部分が片減りし易い。このため、前記作動駒及び中空円筒ラムスリーブの往復動のストローク幅が小さくなり、作動駒及び中空円筒ラムスリーブに装着される工具による歯間清掃機能や根管治療機能が早期に減退してしまうことになる。また、偏心軸の片減りに伴う異音の発生や振動等も懸念され、これが診療効率の低下や患者に対して不快感を与える原因ともなることが予想される。 By the way, the eccentric shaft and the eccentric cylindrical drive pin (hereinafter referred to as the eccentric shaft) in both Patent Documents 1 and 2 are the fitting concave groove and the peripheral groove (hereinafter referred to as the concave groove). It is fitted so that it is in direct contact with the wall. Then, due to the cam action accompanying the eccentric rotation of the eccentric shaft, the groove wall of the concave groove is used as a cam follower, and the operation piece and the hollow cylindrical ram sleeve are orthogonal to the rotation shaft and the shaft of the drive carriage as the shaft rotation drive transmission unit. It is made to reciprocate in the direction to do. That is, since the eccentric shaft as the cam rotates eccentrically while rubbing against the groove wall as the cam follower, the eccentric shaft is severely worn and damaged. In addition, the entire circumference of the circumferential surface of the eccentric shaft rubs against the groove wall, but the rotational radius of the portion far from the rotating shaft and the shaft of the drive carriage is the largest, so the peripheral speed at the time of the rubbing of this portion is the highest. It is large, and this part is easily reduced. For this reason, the stroke width of the reciprocating motion of the operation piece and the hollow cylindrical ram sleeve is reduced, and the interdental cleaning function and the root canal treatment function by the tool attached to the operation piece and the hollow cylindrical ram sleeve are rapidly reduced. It will be. In addition, there are concerns about the generation of noise and vibration associated with the reduction of the eccentric shaft, which is expected to cause a decrease in medical efficiency and cause discomfort to the patient.

また、この種の歯科用ハンドピースの場合、ハンドピース本体（把持部）内の軸回転駆動伝達部の軸回転を円滑に行わせるため、或いは回転部分の発熱を抑えるために、前記ハンドピース本体部から先端ヘッド部内にかけて、潤滑剤が充填され、更には、冷却用空気が供給されるように構成される。然るに、特許文献１に開示された歯科用ハンドピースでは、作動駒が頭部筐体の内壁に接した状態で往復動するため、作動駒及び頭部筐体の内壁が摩耗し易く、前記潤滑剤が冷却空気の供給圧によって、この摩耗による隙間から、頭部筐体における工具の突出部分との間隙を経て、患部に向け噴出されることになる。特に、本特許文献１における工具の装着側とは反対側が蓋体によって封止されているので、前記患部側への吹き出しが顕著となる。一方、特許文献２においては、中空円筒ラムスリーブの往復動方向の前後にはシーリングリングが設けられているので、このような吹き出しが生じる懸念がないが、２個のシーリングリングを必要とするため、部品点数が増大することは不可避である。 Further, in the case of this type of dental handpiece, the handpiece main body is used to smoothly perform the shaft rotation of the shaft rotation drive transmission unit in the handpiece main body (gripping unit) or to suppress the heat generation of the rotating part. It is configured so that the lubricant is filled from the portion to the tip head portion, and further cooling air is supplied. However, the dental handpiece disclosed in Patent Document 1 reciprocates in a state where the operating piece is in contact with the inner wall of the head casing, and therefore, the operating piece and the inner wall of the head casing are easily worn, and the lubrication is performed. Due to the supply pressure of the cooling air, the agent is ejected from the gap due to the wear toward the affected area through a gap with the protruding portion of the tool in the head casing. In particular, since the side opposite to the tool mounting side in Patent Document 1 is sealed with a lid, the blowout toward the affected area becomes prominent. On the other hand, in Patent Document 2, since sealing rings are provided before and after the hollow cylindrical ram sleeve in the reciprocating direction, there is no concern that such blowout may occur, but two sealing rings are required. It is inevitable that the number of parts increases.

本発明は、このような実情に鑑みなされたもので、構造が簡単でありながら、耐久性に優れ、歯間の清掃等に好適に用いられる歯科用ハンドピースを提供することを目的とする。 The present invention has been made in view of such circumstances, and an object of the present invention is to provide a dental handpiece that is simple in structure and excellent in durability and that is suitably used for cleaning between teeth.

本発明に係る歯科用ハンドピースは、軸回転駆動伝達部を内蔵するハンドピース本体部と、前記ハンドピース本体部の先側に連接されたヘッドハウジングを含む先端ヘッド部と、該ヘッドハウジングに前記軸回転駆動伝達部の軸心と直交する方向に往復移動可能に内装され、歯科用工具を着脱自在に挿通保持し得る中空円筒状の工具保持部材とを備えた歯科用ハンドピースであって、前記軸回転駆動伝達部の先端部には、前記軸心と偏心した円柱状カム部が設けられ、前記工具保持部材の外周部には、前記円柱状カム部を嵌挿し得る凹溝が周方向に沿って形成され、前記円柱状カム部には相対摺接可能な円環状軸受が外装され、前記円柱状カム部は該軸受が外装された状態で前記凹溝に嵌挿されており、前記工具保持部材は、前記往復移動方向に沿った前記凹溝の両側において、第１及び第２の滑り軸受を介して前記ヘッドハウジングに前記往復移動可能に支持され、前記第１の滑り軸受は、前記歯科用工具が挿通される側とは反対側のヘッドハウジングの開口部に取付けられる円環状キャップを兼ねるものであることを特徴とする。 A dental handpiece according to the present invention includes a handpiece main body portion including a shaft rotation drive transmission portion, a tip head portion including a head housing connected to the front side of the handpiece main body portion, A dental handpiece provided with a hollow cylindrical tool holding member that is mounted so as to be reciprocally movable in a direction orthogonal to the axis of the shaft rotation drive transmission unit, and is capable of detachably inserting and holding a dental tool, A cylindrical cam portion that is eccentric from the shaft center is provided at a tip portion of the shaft rotation drive transmission portion, and a concave groove in which the cylindrical cam portion can be inserted is circumferentially provided on the outer peripheral portion of the tool holding member. The cylindrical cam portion is externally mounted with an annular bearing capable of relative sliding contact, and the cylindrical cam portion is inserted into the concave groove with the bearing being externally mounted , The tool holding member is Are supported by the head housing through the first and second sliding bearings so as to be able to reciprocate on both sides of the concave groove along the groove, and the first sliding bearing is a side through which the dental tool is inserted. characterized in der Rukoto doubles as an annular cap attached to the opening on the opposite side of the head housing and.

本発明の歯科用ハンドピースにおいて、前記工具保持部材は、前記ヘッドハウジングとの間に設けられる規制手段によって、軸回転不能とされていても良い。 In the dental handpiece of the present invention, the tool holding member may be unable to rotate the shaft by a restricting means provided between the tool housing and the head housing.

また、本発明の歯科用ハンドピースにおいて、前記工具保持部材は、当該工具保持部材の軸心を含み、且つ前記軸回転駆動伝達部の軸心に直交する面に対して対称に形成されていても良い。 In the dental handpiece of the present invention, the tool holding member is formed symmetrically with respect to a plane that includes the axis of the tool holding member and is orthogonal to the axis of the shaft rotation drive transmission unit. Also good.

更に、本発明の歯科用ハンドピースにおいて、前記第１の滑り軸受には、前記ヘッドハウジングの内外に通じる溝が形成されていても良い。 Furthermore, in the dental handpiece of the present invention , the first sliding bearing may be formed with a groove that communicates with the inside and outside of the head housing.

本発明によれば、ハンドピース本体部に内蔵された軸回転駆動伝達部の軸回転に伴い、該軸回転駆動伝達部の先端部に設けられた円柱状カム部が偏心回転する。この円柱状カム部は、前記軸回転駆動伝達部の軸心と直交する方向に往復移動可能に内装された工具保持部材の外周部にその周方向に沿って形成された凹溝に嵌挿されている。前記偏心回転に伴う前記凹溝の溝壁に対する円柱状カム部のカム作用によって、前記工具保持部材は前記軸回転駆動伝達部の軸心と直交する方向に往復移動する。従って、前記工具保持部材の中空円筒部に歯科用工具を挿通保持させれば、歯科用工具も前記回転駆動伝達部の軸心と直交する方向に往復移動し、これによって、歯間の清掃等に供することができる。そして、前記円柱状カム部には円環状軸受が外装されており、前記円柱状カム部は該軸受が外装された状態で前記凹溝に嵌挿されているから、前記カム作用は当該軸受を介してなされ、これによって、円柱状カム部の摩耗の発生が抑えられる。しかも、当該軸受は、前記円柱状カム部に相対摺接可能な状態で外装されているから、円柱状カム部に対して常にフリー回転状態とされる。そのため、前記偏心回転に伴うカム作用において、前記軸受の周面の回転半径の相違による前記凹溝の溝壁に対する擦れ合い時の周速度の異なりが生じ難く、これによって、軸受の外面が擦れ合いによって片減りするおそれがない。従って、本発明の歯科用ハンドピースは、長期の使用においても、歯科用工具の往復移動におけるストローク幅の減退が少なく、また、異音や振動が発生し難く、耐久性に優れたものとなる。 According to the present invention, with the shaft rotation of the shaft rotation drive transmission unit built in the handpiece main body, the columnar cam portion provided at the tip of the shaft rotation drive transmission unit rotates eccentrically. The cylindrical cam portion is fitted into a groove formed along the circumferential direction of the outer periphery of a tool holding member that is mounted so as to be reciprocally movable in a direction perpendicular to the axis of the shaft rotation drive transmission portion. ing. The tool holding member reciprocates in a direction perpendicular to the axis of the shaft rotation drive transmission portion by the cam action of the cylindrical cam portion with respect to the groove wall of the concave groove accompanying the eccentric rotation. Therefore, if a dental tool is inserted and held in the hollow cylindrical portion of the tool holding member, the dental tool also reciprocates in a direction perpendicular to the axis of the rotational drive transmission unit, thereby cleaning between teeth, etc. Can be used. The cylindrical cam portion is covered with an annular bearing, and the cylindrical cam portion is fitted in the concave groove with the bearing being covered. This prevents the occurrence of wear on the cylindrical cam portion. In addition, since the bearing is packaged so as to be capable of relative sliding contact with the cylindrical cam portion, the bearing is always in a free rotating state with respect to the cylindrical cam portion. For this reason, in the cam action associated with the eccentric rotation, the difference in the peripheral speed at the time of rubbing against the groove wall of the concave groove due to the difference in the radius of rotation of the peripheral surface of the bearing hardly occurs. There is no risk of being reduced. Therefore, the dental handpiece of the present invention has excellent durability even when used for a long time with little reduction in stroke width in the reciprocating movement of the dental tool, hardly generating abnormal noise and vibration. .

前記工具保持部材が、前記ヘッドハウジングとの間に設けられる規制手段によって軸回転不能とされている場合、前記円柱状カム部によるカム作用によって前記工具保持部材が前記軸心と直交する方向にのみ移動し、前記往復移動が円滑になされる。特に、歯間清掃用の歯科用ハンドピースの場合、工具保持部材に挿通保持される歯科用工具が軸心対称ではなく、診療態様や診療対象部位に応じて、その軸心回りの角度を変え得るような仕様とされる場合が多い。このような場合、事前に前記適正角度を設定した上で診療作業がなされるが、使用中に不意に前記設定角度が変わるような事態が生じず、術者が意図する診療作業を的確に行うことができる。 When the tool holding member is prevented from rotating by a restricting means provided between the head housing and the tool holding member, the tool holding member is only in a direction perpendicular to the axis by the cam action of the cylindrical cam portion. The reciprocating movement is performed smoothly. In particular, in the case of a dental handpiece for interdental cleaning, the dental tool inserted and held by the tool holding member is not symmetrical with respect to the axial center, and the angle around the axial center is changed according to the medical treatment mode and the site to be treated. There are many cases where the specifications are obtained. In such a case, the medical work is performed after the appropriate angle is set in advance, but the situation where the set angle is unexpectedly changed during use does not occur, and the medical work intended by the surgeon is accurately performed. be able to.

また、前記工具保持部材が、当該工具保持部材の軸心を含み、且つ前記軸回転駆動伝達部の軸心に直交する面に対して対称に形成されている場合、当該工具保持部材が前記面を対称面としてバランスし、前記工具保持部材の当該工具保持部材の軸心に沿った前記往復移動が円滑になされる。 Further, when the tool holding member includes the axis of the tool holding member and is formed symmetrically with respect to a plane perpendicular to the axis of the shaft rotation drive transmission unit, the tool holding member is Are balanced as symmetry planes, and the reciprocation of the tool holding member along the axis of the tool holding member is smoothly performed.

更に、前記工具保持部材が、前記往復移動方向に沿った前記凹溝の両側において、第１及び第２の滑り軸受を介して前記ヘッドハウジングに前記往復移動可能に支持されているものとすれば、両滑り軸受によって、前記往復移動がより円滑になされる。特に、前記円柱状カム部によるカム作用が働く部位（前記凹溝）の両側で、前記２個の滑り軸受で支持されるから、前記往復移動が安定した状態でなされる。しかも、当該工具保持部材がヘッドハウジングに直接支持されていないから、工具保持部材とヘッドハウジングとが擦れ合うことがなく、両者間に擦れ合いによる摩耗等が生じる懸念がない。この場合、前記第１及び第２の滑り軸受のうち第１の滑り軸受が、前記歯科用工具が挿通される側とは反対側のヘッドハウジングの開口部に取付けられる円環状キャップを兼ねるものとすれば、部品点数の増大を抑えることができる。更にこの場合、前記第１の滑り軸受に、前記ヘッドハウジングの内外に通じる溝を形成するようにすれば、前記のように、ハンドピース本体部内当に充填された潤滑剤や供給された冷却空気が、この溝を通じてヘッドハウジングの前記歯科用工具が挿通される側とは反対側に吹き出す。特に、前記第２の滑り軸受によって、歯科用工具側の工具保持部材とヘッドハウジングとの間は封止されているので、この溝からの前記吹き出しが確実になされる。従って、歯科用工具側、即ち、診療対象部位への潤滑剤や冷却空気の吹き出しが生じず、患者に不快感を与えることがない。 Further, the tool holding member is supported on the head housing so as to be reciprocally movable via first and second sliding bearings on both sides of the concave groove along the reciprocating direction. The reciprocating movement is made smoother by the double sliding bearing. In particular, since the two cam bearings support the cam action by the cylindrical cam portion (the concave groove), the reciprocating movement is performed stably. In addition, since the tool holding member is not directly supported by the head housing, the tool holding member and the head housing do not rub against each other, and there is no concern that wear due to the rubbing occurs between the two. In this case, of the first and second sliding bearings, the first sliding bearing also serves as an annular cap attached to the opening of the head housing opposite to the side through which the dental tool is inserted. Then, the increase in the number of parts can be suppressed. Furthermore, in this case, if a groove is formed in the first sliding bearing so as to communicate with the inside and outside of the head housing, as described above, the lubricant filled in the handpiece main body portion and the supplied cooling air are supplied. However, it blows out to the opposite side to the side by which the said dental tool of the head housing is inserted through this groove | channel. In particular, since the space between the tool holding member on the dental tool side and the head housing is sealed by the second sliding bearing, the blowout from the groove is reliably performed. Accordingly, no lubricant or cooling air is blown out to the dental tool side, that is, the medical treatment target site, and the patient is not uncomfortable.

本発明に係る一実施形態の歯科用ハンドピースの全体構成を示す断面図である。It is sectional drawing which shows the whole structure of the dental handpiece of one Embodiment which concerns on this invention. 図１におけるＸ部の拡大断面図である。It is an expanded sectional view of the X section in FIG. 図２におけるＹ−Ｙ線矢視断面図である。FIG. 3 is a cross-sectional view taken along line YY in FIG. 2. におけるＺ−Ｚ線矢視断面図である。FIG. 同実施形態に装着される歯科用工具の一例を示す斜視図である。It is a perspective view which shows an example of the dental tool with which the same embodiment is mounted | worn.

以下、本発明の歯科用ハンドピースの実施の形態について図面に基づき説明する。図１〜図５に示す歯科用ハンドピース１は、歯間或いは歯面清掃用の歯科用ハンドピースであって、該歯科用ハンドピース１は、先端ヘッド部２と、該先端ヘッド部２に連接される細径のネック部３と、該ネック部３に連接され手指によって把持される把持部としてのハンドピース本体部４とを備えている。そして、前記ハンドピース本体部４の基部には、先端ヘッド部２に装着される歯科用（歯間清掃用）工具５を、後記する軸心Ｌ２方向に沿って往復移動させるためのモータユニット６が着脱自在に接続される。ハンドピース１にモータユニット６が連結された状態で歯科用インスツルメント７が構成される。このモータユニット６には、該モータユニット６に内蔵されるマイクロモータ８への電源供給用リード線８１、図示を省略する患部照射用ランプの電源供給用リード線、患部に噴霧注水させるための水管路及びエア管路等を内装するホース６１が連結されている。エア管路には、ハンドピース本体部４及び後記するヘッドハウジング２０内の各機構部を冷却するための空気を供給するエア管路も含まれる。 Hereinafter, embodiments of the dental handpiece of the present invention will be described with reference to the drawings. A dental handpiece 1 shown in FIGS. 1 to 5 is a dental handpiece for interdental or tooth surface cleaning, and the dental handpiece 1 includes a distal end head portion 2 and a distal end head portion 2. A narrow neck portion 3 connected to the neck portion 3 and a handpiece main body portion 4 as a gripping portion connected to the neck portion 3 and gripped by fingers are provided. A motor unit 6 for reciprocating a dental (interdental cleaning) tool 5 attached to the distal end head portion 2 along the axial center L2 direction, which will be described later, is provided at the base portion of the handpiece main body portion 4. Are detachably connected. A dental instrument 7 is configured with the motor unit 6 connected to the handpiece 1. The motor unit 6 includes a power supply lead 81 for the micromotor 8 built in the motor unit 6, a power supply lead for an unillustrated affected part irradiation lamp, and a water pipe for spraying water to the affected part. The hose 61 which connects a path | route, an air pipe line, etc. is connected. The air line includes an air line that supplies air for cooling the handpiece body 4 and each mechanism in the head housing 20 to be described later.

歯科用ハンドピース１は、本体部ハウジング４０にネック部３を介してヘッドハウジング２０が連なってコントラアングル形に形成されている。本体部ハウジング４０内には、ハンドピース本体部の基部にモータユニット６が接続されたときに、マイクロモータ８の出力軸８２にカップリング部９ａを介して連結される第１駆動伝達軸９が軸回転可能に内装されている。第１駆動伝達軸９の先端には第１減速ギヤ機構１０を介して第２駆動伝達軸１１が軸回転可能に連接され、更に、ネック部３に至る部分には、屈折部分の第２減速ギヤ機構１２を介して第３駆動伝達軸（軸回転駆動伝達部）１３が軸回転可能に連接されている。前記第３駆動伝達軸１３は、本体部ハウジング４０内に軸受１４を介して軸回転可能に支持され、その先端部には有底円筒状カムベース１５が圧嵌によって外嵌固設されている。この有底円筒状カムベース１５の先端部に、前記第３駆動伝達軸１３の軸心Ｌ１と偏心して設けられた円柱状カム部１６が一体に形成されている。前記有底円筒状カムベース１５には、内筒部と外部とが通じる通気孔１５ａが設けられており、該通気孔１５ａは、当該有底円筒状カムベース１５を前記第３駆動伝達軸１３の先端に外嵌させる際の空気抜きとされている。前記円柱状カム部１６には、円環状（円筒状）軸受１７が、同心且つ相対摺接可能（フリー回転可能）に外装されている。前記本体部ハウジング４０には、前記モータユニット６に設けられた不図示の照明用ランプ（例えば、ＬＥＤ）が発する照明光を前記ネック部３にまで導光する導光体（例えば、光ファイバ）１８が内装されている。この導光体１８によって導光された照明光は、その出光端１８ａから前記歯間清掃用工具５の先端部に向け出射される。また、本体部ハウジング４０からヘッドハウジング２０の空間部には、前記ホース６１に内装される不図示のエア管路から冷却用空気が供給されるようになされている。 The dental handpiece 1 is formed in a contra-angle shape with the head housing 20 connected to the main body housing 40 via the neck portion 3. A first drive transmission shaft 9 is connected to the output shaft 82 of the micromotor 8 via a coupling portion 9a when the motor unit 6 is connected to the base of the handpiece main body in the main body housing 40. The interior is rotatable. A second drive transmission shaft 11 is connected to the tip of the first drive transmission shaft 9 via a first reduction gear mechanism 10 so as to be capable of rotating the shaft. A third drive transmission shaft (shaft rotation drive transmission portion) 13 is connected via a gear mechanism 12 so as to be rotatable. The third drive transmission shaft 13 is supported in the main body housing 40 through a bearing 14 so as to be axially rotatable, and a bottomed cylindrical cam base 15 is externally fitted and fixed to the front end portion thereof by press fitting. A cylindrical cam portion 16 that is provided eccentrically with the axis L1 of the third drive transmission shaft 13 is integrally formed at the tip of the bottomed cylindrical cam base 15. The bottomed cylindrical cam base 15 is provided with a vent hole 15a through which the inner tube portion communicates with the outside. The vent hole 15a connects the bottomed cylindrical cam base 15 to the tip of the third drive transmission shaft 13. It is used as an air vent when fitted on the outside. An annular (cylindrical) bearing 17 is mounted on the columnar cam portion 16 so as to be concentric and relatively slidable (freely rotatable). The main body housing 40 has a light guide (for example, an optical fiber) that guides illumination light emitted from an unillustrated illumination lamp (for example, LED) provided in the motor unit 6 to the neck 3. 18 are decorated. The illumination light guided by the light guide 18 is emitted from the light exit end 18a toward the tip of the interdental cleaning tool 5. Cooling air is supplied from the main body housing 40 to the space of the head housing 20 from an air pipe (not shown) built in the hose 61.

先端ヘッド部２のヘッドハウジング２０には、前記歯間清掃用工具５を着脱自在に挿通保持し得る工具保持部材１９が、当該工具保持部材１９の軸心Ｌ２方向に沿って往復移動可能に内装されている。該工具保持部材１９は、中空円筒状の本体部１９０と、該本体部本体部１９０の外周部に、前記軸心Ｌ２方向に沿って隔設された一対の鍔部１９１，１９２とを含む。以下では、便宜上前記軸心Ｌ２に沿って、図１〜図３における紙面の上側を上、下側を下と言う。この一対の鍔部１９１，１９２の間隔は、前記軸受１７を外装した状態の前記円柱状カム部１６が、若干の遊びをもって嵌挿し得る大きさ、即ち、軸受１７の外径より若干大とされる。この上下の鍔部１９１，１９２は、前記本体部１９０の周面から前記軸心Ｌ２を回転対称軸として１８０°をなす方向に延びる同幅の隔壁１９３，１９４によって連結されている。そして、この隔壁１９３，１９４によって画成された鍔部１９１，１９２間の空間部によって、周方向に沿った２個の凹溝１９５，１９６が形成される。前記隔壁１９３，１９４の遠心方向両端面の中央部と、この部位に対応する鍔部１９１，１９２の周縁部とには、前記本体部１９０の軸心Ｌ２に沿って上下に連続する断面円弧形状の縦溝１９７，１９８が形成されている。この縦溝１９７，１９８は、後記する規制手段２５，２６を構成する第１のキー溝とされる。また、前記ヘッドハウジング２０の内壁部であって、前記本体部１９０の軸心Ｌ２を含み、前記第３駆動伝達軸１３の軸心Ｌ１に直交する仮想面Ｆ（図４参照）が交差する部分には、該仮想面Ｆを対称面として、前記第１のキー溝１９７，１９８と略同曲率の縦溝２１，２２が形成されている。該縦溝２１，２２は、後記する規制手段２５，２６を構成する第２のキー溝とされ、ヘッドハウジング２０の上端開口部２０ａからヘッドハウジング２０の中程にまで及んでいる。 A tool holding member 19 capable of detachably inserting and holding the interdental cleaning tool 5 is provided in the head housing 20 of the tip head portion 2 so as to reciprocate along the direction of the axis L2 of the tool holding member 19. Has been. The tool holding member 19 includes a hollow cylindrical main body portion 190 and a pair of flange portions 191 and 192 provided on the outer peripheral portion of the main body portion main body portion 190 along the direction of the axis L2. Hereinafter, for the sake of convenience, along the axis L2, the upper side of the paper in FIGS. The distance between the pair of flange portions 191 and 192 is such that the columnar cam portion 16 with the bearing 17 mounted can be fitted and inserted with some play, that is, slightly larger than the outer diameter of the bearing 17. The The upper and lower flange portions 191 and 192 are connected to each other by partition walls 193 and 194 having the same width extending from the peripheral surface of the main body 190 in the direction of 180 ° with the axis L2 as a rotational symmetry axis. And the two recessed grooves 195 and 196 along the circumferential direction are formed by the space part between the collar parts 191 and 192 defined by the partition walls 193 and 194. The central part of the both end faces in the centrifugal direction of the partition walls 193 and 194 and the peripheral parts of the flange parts 191 and 192 corresponding to this part have a circular arc shape that continues vertically along the axis L2 of the main body part 190. Vertical grooves 197 and 198 are formed. The longitudinal grooves 197 and 198 serve as first key grooves constituting restricting means 25 and 26 described later. Further, the inner wall portion of the head housing 20 is a portion that includes the axis L2 of the main body 190 and intersects with a virtual plane F (see FIG. 4) orthogonal to the axis L1 of the third drive transmission shaft 13. The vertical grooves 21 and 22 having substantially the same curvature as the first key grooves 197 and 198 are formed with the virtual plane F as a symmetry plane. The longitudinal grooves 21 and 22 serve as second key grooves constituting restricting means 25 and 26, which will be described later, and extend from the upper end opening 20a of the head housing 20 to the middle of the head housing 20.

前記工具保持部材１９は、上下の円環状滑り軸受２７，２８によって、前記ヘッドハウジング２０内で上下移動可能、且つ、後記する規制手段２５，２６によって、前記軸心Ｌ２回りの軸回転不能に支持されている。上側の第１滑り軸受２７は、雄ねじ部２７ａを備えており、前記ヘッドハウジング２０の上端開口部２０ａの近傍に設けられた雌ねじ部２０ｂに、前記雄ねじ部２７ａを螺合することによって、ヘッドハウジング２０に取付けられる。また、下側の第２の滑り軸受２８は雄ねじ部２８ａを備えており、前記ヘッドハウジング２０の下端開口部２０ｃの近傍に設けられた雌ねじ部２０ｄに、前記雄ねじ部２８ａを螺合することによって、ヘッドハウジング２０に取付けられる。第１の滑り軸受２７は、ヘッドハウジング２０の上端開口部２０ａに取付けられるキャップを兼ねる。また、該滑り軸受２７の内周面の１８０°対向する位置には、ヘッドハウジング２０の外部と、工具保持部材１９の外側に位置するヘッドハウジング２０の内部とに通じる２個の溝２７ｂ，２７ｂが設けられている。前記第２のキー溝２１，２２は、前記雌ねじ部２０ｂにおいても形成されており、該雌ねじ部２０ｂは、前記第２のキー溝２１，２２に対応する部分において、周方向に分断されている（図３参照）。 The tool holding member 19 can be moved up and down in the head housing 20 by upper and lower annular slide bearings 27 and 28, and supported by the restricting means 25 and 26 described later so as not to rotate about the axis L2. Has been. The upper first sliding bearing 27 includes a male screw portion 27a, and the male screw portion 27a is screwed into a female screw portion 20b provided in the vicinity of the upper end opening 20a of the head housing 20, whereby the head housing. 20 is attached. The lower second sliding bearing 28 includes a male screw portion 28a, and the male screw portion 28a is screwed into a female screw portion 20d provided in the vicinity of the lower end opening 20c of the head housing 20. Is attached to the head housing 20. The first sliding bearing 27 also serves as a cap attached to the upper end opening 20 a of the head housing 20. In addition, two grooves 27 b and 27 b that communicate with the outside of the head housing 20 and the inside of the head housing 20 located outside the tool holding member 19 are positioned at 180 ° on the inner peripheral surface of the sliding bearing 27. Is provided. The second key grooves 21 and 22 are also formed in the female screw portion 20b, and the female screw portion 20b is divided in the circumferential direction at a portion corresponding to the second key grooves 21 and 22. (See FIG. 3).

前記のように構成される工具保持部材１９を前記ヘッドハウジング２０に組付け、歯科用ハンドピース１を組立てる要領について説明する。先ず、前記第２の滑り軸受２８を、前記雌ねじ部２０ｄ及び雄ねじ部２８ａの螺合によりヘッドハウジング２０に取付ける。図２に示す符号２８ｂは、この螺合操作の際に、滑り軸受２８をドライバー等の工具で前記軸心Ｌ２の回りに捩回するための工具当て用の溝である。次いで、工具保持部材１９を、ヘッドハウジング２０の上端開口部２０ａより挿入し、前記第２の滑り軸受２８に、本体部１９０の下部を、その下端部が前記ヘッドハウジング２０の下端開口部２０ｃより下側に突出するよう嵌挿する。この状態で、工具保持部材１９を、前記第１のキー溝１９７，１９８が、ヘッドハウジング２０側の第２のキー溝２１，２２にそれぞれ整合するよう、手指で前記軸心Ｌ２回りに回転させて位置調整をする。この第１のキー溝１９７，１９８及び第２のキー溝２１，２２間に、これらキー溝の曲率と略同曲率の円柱形のキー部材２３，２４を上から差し込む。これによって、工具保持部材１９の、前記軸心Ｌ２回りの軸回転が不能とされる。即ち、第１のキー溝１９７、キー部材２３及び第２のキー溝２１によって、前記規制手段２５が構成され、第１のキー溝１９８、キー部材２４及び第２のキー溝２２によって、前記規制手段２６が構成される。そして、第１の滑り軸受２７を、前記雌ねじ部２０ｂ及び雄ねじ部２７ａの螺合によりヘッドハウジング２０に取付ける。図３に示す符号２７ｃは、この螺合操作の際に、スパナ等の工具を宛がうためのフライスカット部である。この螺合取付によって、第１の滑り軸受２７は、前記工具保持部材１９における本体部１９０の上部に外装される。 A procedure for assembling the dental handpiece 1 by assembling the tool holding member 19 configured as described above to the head housing 20 will be described. First, the second sliding bearing 28 is attached to the head housing 20 by screwing the female screw portion 20d and the male screw portion 28a. Reference numeral 28b shown in FIG. 2 is a tool contact groove for twisting the slide bearing 28 around the axis L2 with a tool such as a screwdriver during the screwing operation. Next, the tool holding member 19 is inserted from the upper end opening 20 a of the head housing 20, the lower portion of the main body 190 is inserted into the second sliding bearing 28, and the lower end thereof is from the lower end opening 20 c of the head housing 20. Insert so that it protrudes downward. In this state, the tool holding member 19 is rotated around the axis L2 with fingers so that the first key grooves 197 and 198 are aligned with the second key grooves 21 and 22 on the head housing 20 side, respectively. Adjust the position. Between the first key grooves 197 and 198 and the second key grooves 21 and 22, cylindrical key members 23 and 24 having substantially the same curvature as the key grooves are inserted from above. As a result, the tool holding member 19 cannot be rotated about the axis L2. That is, the restricting means 25 is constituted by the first key groove 197, the key member 23, and the second key groove 21, and the restricting means 25 is constituted by the first key groove 198, the key member 24, and the second key groove 22. Means 26 are configured. Then, the first plain bearing 27 is attached to the head housing 20 by screwing the female screw portion 20b and the male screw portion 27a. Reference numeral 27c shown in FIG. 3 is a milling cut portion for attaching a tool such as a spanner during the screwing operation. The first sliding bearing 27 is externally mounted on the upper part of the main body 190 of the tool holding member 19 by this screwing attachment.

これによって、工具保持部材１９のヘッドハウジング２０に対する組付けが完了する。この組付け状態では、前記２個の規制手段２５，２６によって、当該工具保持部材１９の前記軸心Ｌ２回りの軸回転は不能とされる。しかし、上下の滑り軸受２７，２８によって、当該工具保持部材１９の前記軸心Ｌ２に沿った上下の往復移動は可能とされる。また、前記第１のキー溝１９７，１９８と第２のキー溝２１，２２とがそれぞれ整合した位置で、キー部材２３，２４によって、工具保持部材１９が前記軸心Ｌ２回りの軸回転が不能の状態に維持される。この維持状態では、当該工具保持部材１９の前記各部位の形成態様によって、該工具保持部材１９が、前記軸心Ｌ２を含み、前記第３駆動伝達軸１３の軸心Ｌ１に直交する仮想面Ｆに対して対称とされる。これによって、前記仮想面Ｆを対称面として上下の鍔部１９１，１９２による同形状の凹溝１９５，１９６が対称関係で位置することになる。従って、工具保持部材１９のヘッドハウジング２０に対する組付け時に、前記第１のキー溝１９７，１９８と第２のキー溝２１，２２との整合が図４に示す例とは１８０°逆になっても支障がない。即ち、次にハンドピース本体４に先端ヘッド部２を接続させる際、前記円柱状カム部１６が凹溝１９５，１９６のいずれに嵌挿されても、後記する円柱状カム部１６による回転運動から直線運動への動力伝達機能が同様に発揮される。 Thereby, the assembly of the tool holding member 19 to the head housing 20 is completed. In this assembled state, the two restricting means 25 and 26 make it impossible for the tool holding member 19 to rotate around the axis L2. However, the upper and lower sliding bearings 27 and 28 allow the tool holding member 19 to reciprocate up and down along the axis L2. In addition, the tool holding member 19 cannot be rotated about the axis L2 by the key members 23 and 24 at the positions where the first key grooves 197 and 198 and the second key grooves 21 and 22 are aligned. Is maintained. In this maintenance state, the tool holding member 19 includes the shaft center L2 and the virtual plane F perpendicular to the shaft center L1 of the third drive transmission shaft 13 according to the formation mode of each part of the tool holding member 19. Is symmetric. Accordingly, the concave grooves 195 and 196 having the same shape formed by the upper and lower flange portions 191 and 192 are positioned in a symmetrical relationship with the virtual plane F as a symmetry plane. Therefore, when the tool holding member 19 is assembled to the head housing 20, the alignment of the first key grooves 197, 198 and the second key grooves 21, 22 is 180 ° opposite to the example shown in FIG. There is no problem. That is, when the tip head portion 2 is connected to the handpiece body 4 next time, even if the cylindrical cam portion 16 is inserted into any one of the concave grooves 195 and 196, the rotational motion by the cylindrical cam portion 16 described later is prevented. The power transmission function for linear motion is also demonstrated.

前記のように工具保持部材１９が組付けられたヘッドハウジング２０は、事前に前記各機構部が組付けられたハンドピース本体部４の本体部ハウジング４０に接続される。この接続の際、前記軸受１７を外装させた状態の前記円柱状カム部１６を前記凹溝１９５，１９６のいずれかに嵌挿させる。これによって、歯科（歯間清掃）用ハンドピース１の組立が完了する。そして、当該歯間清掃用ハンドピース１の使用に際しては、図１、図２及び図５に示すような歯間清掃用工具５が、前記工具保持部材１９における中空円筒状の本体部１９０の内筒部にその下端部より圧入され、この圧入状態で挿通保持される。該歯間清掃用工具５は、該本体部１９０に挿通保持される円柱状のシャンク部５１と、その先側に連なるヘラ形状の作用部５２とよりなり、該シャンク部５１には、前記本体部１９０の内径より若干大径のフリクション環部５１ａ，５１ｂが形成されている。従って、当該シャンク部５１を前記本体部１９０に挿通する際、このフリクション環部５１ａ，５１ｂが本体部１９０の内壁部に圧接し、この圧接によるフリクション作用によって、工具保持部材１９に対して脱落することなく保持される。 The head housing 20 to which the tool holding member 19 is assembled as described above is connected to the main body housing 40 of the handpiece main body 4 to which each of the above-mentioned mechanism units has been assembled in advance. At the time of this connection, the cylindrical cam portion 16 in a state where the bearing 17 is sheathed is fitted into one of the concave grooves 195 and 196. Thereby, the assembly of the handpiece 1 for dentistry (interdental cleaning) is completed. When the interdental cleaning handpiece 1 is used, the interdental cleaning tool 5 as shown in FIGS. 1, 2, and 5 is disposed inside the hollow cylindrical main body 190 of the tool holding member 19. It is press-fitted into the cylinder part from its lower end, and is inserted and held in this press-fitted state. The interdental cleaning tool 5 includes a columnar shank portion 51 inserted and held in the main body portion 190 and a spatula-shaped action portion 52 connected to the front side thereof, and the shank portion 51 includes the main body portion 51. Friction ring portions 51a and 51b having a diameter slightly larger than the inner diameter of the portion 190 are formed. Therefore, when the shank 51 is inserted into the main body 190, the friction ring portions 51a and 51b come into pressure contact with the inner wall of the main body 190, and drop off from the tool holding member 19 by the friction action caused by the pressure contact. Retained without.

また、前記シャンク部５１における前記作用部５２との連接部位には、１８０°対向する関係で同形状の２個の位置決用のボス５３，５３が突設されている。一方、前記工具保持部材１９における本体部１９０の下端部には、複数個（偶数個）の切欠部１９０ａ…が、１８０°対向する位置に対をなすように形成されている。この複数個の切欠部１９０ａ…は全て同形状であって、前記ボス５３，５３を受容し得る形状とされている。歯間清掃用工具５は、その作用部５２が図示のように歯間に挿入し得るようなヘラ形状とされているから、診療対象部位に応じて作用部５２のヘラ形状部の向き（前記軸心Ｌ２回りの角度）を変える必要がある。従って、前記ボス５３，５３を前記切欠部１９０ａ…のいずれかの対に整合するようにして、歯間清掃用工具５を工具保持部材１９に挿通保持させることによって、このような対応が任意になされる。 Further, two bosses 53, 53 having the same shape projectingly project from the connecting portion of the shank portion 51 with the action portion 52 so as to face each other by 180 °. On the other hand, a plurality (even number) of notches 190a... Are formed at the lower end portion of the main body 190 of the tool holding member 19 so as to make a pair at positions opposed to each other by 180 °. The plurality of notches 190a... Have the same shape and can receive the bosses 53. The interdental cleaning tool 5 has a spatula shape in which the action part 52 can be inserted between teeth as shown in the figure, so that the direction of the spatula-shaped part of the action part 52 according to the medical site (see above) It is necessary to change the angle around the axis L2. Therefore, such correspondence can be made arbitrarily by inserting and holding the interdental cleaning tool 5 in the tool holding member 19 so that the bosses 53 and 53 are aligned with any pair of the notches 190a. Made.

前記のように歯間清掃用工具５が前記工具保持部材１９に挿通保持された状態で、前記マイクロモータ８のスイッチ（不図示）がオンとされると、その出力軸８２の軸回転が第１駆動伝達軸９及び第２駆動伝達軸１１を経て第３駆動伝達軸１３に伝達され、該第３駆動伝達軸１３はその軸心Ｌ１回りに軸回転する。該第３駆動伝達軸１３の先端部には円柱状カムベース１５が固定されており、この円柱状カム部材１５には、前記第３駆動伝達軸１３の軸心Ｌ１と偏心する軸心Ｌ３を備える円柱状の円柱状カム部１６が一体に設けられている。従って、前記第３駆動伝達軸１３の軸心Ｌ１回りの軸回転によって、前記円柱状カム部１６は、その軸心Ｌ３の前記軸心Ｌ１に対する偏心幅ｄを回転半径として、前記軸心Ｌ１の回りに偏心回転する。この円柱状カム部１６の偏心回転に伴い、軸受１７を介した円柱状カム部１６が、凹溝１９５を構成する上下の鍔部１９１，１９２の内面に対して、該内面をカムフォロアとして作用する。このカム作用によって、工具保持部材１９が実線位置と２点鎖線位置との間で、前記軸心Ｌ２の方向に沿って上下に往復移動する。この工具保持部材１９の往復移動に伴い、該工具保持部材１９に挿通保持された歯間清掃用工具５も一体に上下に往復移動する。従って、歯間に前記作用部５２を挿入させた状態でこの動作を行えば、歯間に溜まっている歯垢や歯石等が除去される。 When the switch (not shown) of the micromotor 8 is turned on in the state where the interdental cleaning tool 5 is inserted and held in the tool holding member 19 as described above, the shaft rotation of the output shaft 82 is changed to the first. The first drive transmission shaft 9 and the second drive transmission shaft 11 are transmitted to the third drive transmission shaft 13, and the third drive transmission shaft 13 rotates about its axis L1. A cylindrical cam base 15 is fixed to the tip of the third drive transmission shaft 13, and the cylindrical cam member 15 is provided with an axis L 3 that is eccentric from the axis L 1 of the third drive transmission shaft 13. A cylindrical columnar cam portion 16 is integrally provided. Accordingly, the axial rotation of the third drive transmission shaft 13 around the axis L1 causes the cylindrical cam portion 16 to have an eccentric width d of the axis L3 with respect to the axis L1 as a rotation radius. It rotates eccentrically around. Along with the eccentric rotation of the cylindrical cam portion 16, the cylindrical cam portion 16 via the bearing 17 acts on the inner surfaces of the upper and lower flange portions 191 and 192 constituting the concave groove 195 as cam followers. . This cam action causes the tool holding member 19 to reciprocate up and down along the direction of the axis L2 between the solid line position and the two-dot chain line position. As the tool holding member 19 reciprocates, the interdental cleaning tool 5 inserted and held by the tool holding member 19 also moves up and down integrally. Therefore, if this operation is performed with the action portion 52 inserted between the teeth, plaque, tartar and the like accumulated between the teeth are removed.

前記偏心回転時に、円柱状カム部１６は、軸受１７を介して前記鍔部１９１，１９２の内面に作用するから、円柱状カム部１６の外周部に擦れ合いによる摩耗及び損傷等が生じる懸念がなく、耐久性が向上する。また、軸受１７の外周部において、前記軸心Ｌ１から最も遠い部分の回転半径が最も大きいが、該軸受１７は円柱状カム部１６に対してフリー回転可能に外装されているから、軸受１７における最も回転半径の大きい部分が絶えず変動する。従って、円柱状カム部１６の前記偏心回転に伴うカム作用において、前記軸受１７の外周面の回転半径の相違による鍔部１９１，１９２の内面に対する擦れ合い時の周速度の最も大きな部分も絶えず変動し、これによって、軸受１７の外周面に、擦れ合いによる、いわゆる片減りを生じる懸念がない。従って、長期の使用によっても、歯間清掃用工具５の往復移動ストロークの減退が少なく、また、振動や異音の発生が抑制され、患者に対して不快感を与えることがない。また、工具保持部材１９は、ヘッドハウジング２０に内装された状態では、前記仮想面Ｆに対して対称となるように構成されているから、前記軸心Ｌ２に沿った上下の往復移動が、バランス良く、且つ、円滑になされる。 During the eccentric rotation, the cylindrical cam portion 16 acts on the inner surfaces of the flange portions 191 and 192 via the bearings 17, so there is a concern that the outer peripheral portion of the cylindrical cam portion 16 may be worn and damaged due to friction. And durability is improved. Further, in the outer peripheral portion of the bearing 17, the radius of rotation of the portion farthest from the axis L <b> 1 is the largest, but the bearing 17 is externally mounted on the cylindrical cam portion 16 so as to be freely rotatable. The part with the largest turning radius constantly fluctuates. Therefore, in the cam action that accompanies the eccentric rotation of the cylindrical cam portion 16, the portion with the largest peripheral speed at the time of rubbing against the inner surfaces of the flanges 191 and 192 due to the difference in the rotation radius of the outer peripheral surface of the bearing 17 constantly varies. As a result, there is no concern that the outer peripheral surface of the bearing 17 is so-called reduced due to friction. Therefore, even when used for a long period of time, the reciprocating stroke of the interdental cleaning tool 5 is less likely to be reduced, and the occurrence of vibrations and noises is suppressed, so that the patient does not feel uncomfortable. In addition, since the tool holding member 19 is configured to be symmetric with respect to the virtual plane F in the state of being housed in the head housing 20, the vertical reciprocation along the axis L2 is balanced. Good and smooth.

前記工具保持部１９及び歯間清掃用工具５の上下往復移動動作によって前記歯間清掃診療を行う際、前記不図示の水管路及びエア管路からの水及び空気を歯間清掃用工具５の作用部５２及び診療対象部位に向けて噴霧させ、作用部５２の冷却及び清掃屑の除去等がなされる。また、前記モータユニット６に内蔵される不図示の患部照射用ランプからの光を前記導光体１８を導光させ、出光端１８ａから前記歯間清掃用工具５の先端部に向け出射させて、診療対象部位を明るくした状態で前記清掃診療がなされる。更に、前記清掃診療動作時には、前記ホース６１に内装される不図示のエア管路からハンドピース本体部４及びヘッドハウジング２０内の各機構部を冷却するための空気が、ハンドピース本体部４及びヘッドハウジング２０内の各機構部との空間部に供給される。前記各機構部の組付、組立及びメンテナンス時には、これら機構部の動作が円滑になされるよう潤滑剤が充填されるが、この冷却用空気の供給に伴い、潤滑剤が冷却用空気と共にヘッドハウジング２０内に流入する。前記第１の滑り軸受２７には、ヘッドハウジング２０の内外に通じる溝２７ｂ，２７ｂが形成されているから、ヘッドハウジング２０内に流入した潤滑剤と空気との混合体は、この溝２７ｂ，２７ｂからヘッドハウジング２０の上側の外部に逐次排出される。ヘッドハウジング２０の下側の開口部２０ｃは、実質上第２の滑り軸受２８によって封止されているから、この混合体が診療対象部位に向け吹き出されることがない。 When performing the interdental cleaning medical treatment by the vertical reciprocating movement of the tool holding unit 19 and the interdental cleaning tool 5, water and air from the water conduit and the air conduit (not shown) are supplied to the interdental cleaning tool 5. It sprays toward the action part 52 and a medical treatment object site | part, cooling of the action part 52, removal of cleaning waste, etc. are made. Further, light from an unillustrated affected area irradiation lamp built in the motor unit 6 is guided through the light guide 18 and emitted from the light exit end 18a toward the tip of the interdental cleaning tool 5. The cleaning treatment is performed in a state where the medical treatment target portion is brightened. Further, during the cleaning medical operation, air for cooling the handpiece main body 4 and each mechanism in the head housing 20 from an air pipe (not shown) built in the hose 61 is supplied to the handpiece main body 4 and It is supplied to a space part with each mechanism part in the head housing 20. During assembly, assembly, and maintenance of each of the mechanism parts, a lubricant is filled so that the operations of these mechanism parts are performed smoothly. With the supply of the cooling air, the lubricant is combined with the cooling air in the head housing. 20 flows in. Since the first sliding bearing 27 is formed with grooves 27b and 27b communicating with the inside and outside of the head housing 20, the mixture of the lubricant and air that has flowed into the head housing 20 is formed in the grooves 27b and 27b. Are sequentially discharged to the outside of the upper side of the head housing 20. Since the opening 20c on the lower side of the head housing 20 is substantially sealed by the second sliding bearing 28, the mixture is not blown out toward the medical site.

歯間清掃用工具５の先端ヘッド部２に対する装着状態では、図１に示すように、その上端部がヘッドハウジング２０の上方に突出している。従って、診療作業中に歯間清掃用工具５の向きを変えたり、歯間清掃用工具５を交換したりする際は、この突出部分の上端面を前記軸心Ｌ２方向に沿って、手指で強く押すか、ハンマー等で軽く叩くようにすれば、歯間清掃用工具５を先端ヘッド部２から簡易に取外すことができる。 When the interdental cleaning tool 5 is attached to the distal end head portion 2, the upper end portion protrudes above the head housing 20 as shown in FIG. 1. Therefore, when changing the direction of the interdental cleaning tool 5 or replacing the interdental cleaning tool 5 during the medical work, the upper end surface of the protruding portion is moved along the direction of the axis L2 with fingers. The interdental cleaning tool 5 can be easily removed from the distal end head portion 2 if it is strongly pressed or lightly hit with a hammer or the like.

尚、前記の実施形態では、歯間清掃用ハンドピース１を例に採って説明したが、歯科用工具が軸回転駆動部の軸心に直交する方向に往復移動するよう構成される他の歯科用ハンドピースにも好ましく適用される。また、円柱状カム部１６が作用する凹溝１９５，１９６が、上下の鍔部１９１，１９２で構成される例について述べたが、これに限らず、工具保持部材１９の本体部１９０に直接凹設されたものであっても良い。更に、例示した歯間清掃用工具５は、図例の形状ものに限定されず、他の形状のものも採用可能である。 In the above-described embodiment, the interdental cleaning handpiece 1 has been described as an example. However, the dental tool is configured to reciprocate in a direction perpendicular to the axis of the shaft rotation driving unit. It is preferably applied to a handpiece for use. In addition, the example in which the concave grooves 195 and 196 on which the cylindrical cam portion 16 acts is composed of the upper and lower flange portions 191 and 192 has been described. It may be provided. Furthermore, the illustrated interdental cleaning tool 5 is not limited to the shape shown in the figure, and other shapes can also be employed.

１歯間清掃用（歯科用）ハンドピース
２先端ヘッド部
２０ヘッドハウジング
２０ａ開口部
４ハンドピース本体部
５歯間清掃用（歯科用）工具
１３第３駆動伝達軸（軸回転駆動伝達部）
１６円柱状カム部
１７軸受
１９工具保持部材
１９５，１９６凹溝
２５，２６規制手段
２７第１の滑り軸受
２７ｂ溝
２８第２の滑り軸受
Ｌ１第３駆動伝達軸（軸回転駆動伝達部）の軸心
Ｌ２工具保持部材の軸心
Ｌ３円柱状カム部の軸心
Ｆ仮想面（Ｌ２を含むＬ１に直交する面） DESCRIPTION OF SYMBOLS 1 Interdental cleaning (dental) handpiece 2 Tip head part 20 Head housing 20a Opening part 4 Handpiece main body part 5 Interdental cleaning (dental) tool 13 3rd drive transmission shaft (shaft rotation drive transmission part)
16 cylindrical cam portion 17 bearing 19 tool holding member 195, 196 concave groove 25, 26 restricting means 27 first sliding bearing 27b groove 28 second sliding bearing L1 shaft of third drive transmission shaft (shaft rotation drive transmission portion) Center L2 Center axis of tool holding member L3 Center axis of cylindrical cam portion F Virtual plane (plane orthogonal to L1 including L2)

Claims

A handpiece main body portion including a shaft rotation drive transmission portion, a tip head portion including a head housing connected to the front side of the handpiece main body portion, and the head housing orthogonal to the axis of the shaft rotation drive transmission portion A dental handpiece provided with a hollow cylindrical tool holding member that is reciprocally movable in a direction to be inserted and can detachably insert and hold a dental tool,
A cylindrical cam portion that is eccentric with the shaft center is provided at the tip of the shaft rotation drive transmission portion,
On the outer peripheral portion of the tool holding member, a concave groove into which the cylindrical cam portion can be inserted is formed along the circumferential direction.
An annular bearing capable of relative sliding contact is externally mounted on the cylindrical cam portion, and the cylindrical cam portion is fitted in the concave groove in a state where the bearing is externally mounted ,
The tool holding member is supported by the head housing via the first and second sliding bearings on both sides of the concave groove along the reciprocating movement direction so as to be reciprocally movable. , dental handpiece, characterized in der Rukoto doubles as an annular cap attached to the opening of the opposite head housing to the side of the dental tool is inserted.

The dental handpiece according to claim 1,
The dental handpiece, wherein the tool holding member is made non-rotatable by a restricting means provided between the head holding housing and the tool holding member.

The dental handpiece according to claim 2,
The dental handpiece, wherein the tool holding member includes an axis of the tool holding member and is symmetrical with respect to a plane orthogonal to the axis of the shaft rotation drive transmission unit.

The dental handpiece according to claim 3,
A dental handpiece, wherein the restricting means is provided at two locations.

The dental handpiece according to any one of claims 1 to 4 ,
A dental handpiece, wherein the first sliding bearing is formed with a groove that communicates with the inside and outside of the head housing.