JPH11332894A - Rotary chattering prevention structure - Google Patents

Rotary chattering prevention structure

Info

Publication number
JPH11332894A
JPH11332894A JP14973298A JP14973298A JPH11332894A JP H11332894 A JPH11332894 A JP H11332894A JP 14973298 A JP14973298 A JP 14973298A JP 14973298 A JP14973298 A JP 14973298A JP H11332894 A JPH11332894 A JP H11332894A
Authority
JP
Japan
Prior art keywords
shaft
collars
rod
collar
parallel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP14973298A
Other languages
Japanese (ja)
Inventor
Kazuaki Kato
和昭 加藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bristol Myers Squibb KK
Original Assignee
Bristol Myers Squibb KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Bristol Myers Squibb KK filed Critical Bristol Myers Squibb KK
Priority to JP14973298A priority Critical patent/JPH11332894A/en
Publication of JPH11332894A publication Critical patent/JPH11332894A/en
Pending legal-status Critical Current

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  • Mutual Connection Of Rods And Tubes (AREA)
  • Prostheses (AREA)

Abstract

PROBLEM TO BE SOLVED: To realize a rotary chattering prevention structure which enables fixing of a member arranged rotatable on a shaft with respect to at least one plane formed on the shaft without chattering. SOLUTION: This structure comprises a shaft 20 on which two planes 20a and 20b are formed parallel with the center axis thereof and two collars 21 and 22 which has a hole 23 where two planes 23a and 23b are formed on the internal surface thereof to allow loosely fitting thereof onto the shaft 20. Each one of end faces of the collars 21 and 22 is formed respectively on inclined surfaces 24 each containing a straight line orthogonal to the center axis of the collars 21 and 22 while being parallel with the two planes 23a and 23b so that the two collars 21 and 22 are inserted onto the shaft 20 with the inclined surfaces 24 facing each other. The two collars 21 and 22 are pressed together so that the inclined surfaces 24 are slid in the direction opposite to each other to remove chattering between the shaft 20 and the collars 21 and 22.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は回転ガタ防止構造に
関する。詳しくは、2面を有する軸に対して遊嵌し且つ
回転不可能に設けられた部材を、軸に対してガタ無く固
定することができる回転ガタ防止構造に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation play preventing structure. More specifically, the present invention relates to a rotation backlash preventing structure capable of fixing a member which is loosely fitted to a shaft having two surfaces and is not rotatable to the shaft without play.

【0002】[0002]

【従来の技術】従来、回転ガタ防止構造を必要とする例
として図4に示すアジャスタブルカップポジショナーに
例をとり説明する。このアジャスタブルカップポジショ
ナーは寛臼蓋の再建手術(人工股関節置換手術)時に用
いられる位置決めゲージであって、水平位置にある第1
のロッド1の一端に第1のハンドル2が垂直に且つT字
状に結合され、他端に第2のロッド3が垂直に且つT字
状に結合され、該第2のロッド3の一端には第2のハン
ドル4が水平に且つ第1のロッド1に直交するように結
合されている。
2. Description of the Related Art Conventionally, an adjustable cup positioner shown in FIG. This adjustable cup positioner is a positioning gauge used in an acetabular reconstruction operation (artificial hip replacement surgery), and is a first position gauge in a horizontal position.
A first handle 2 is vertically and T-shaped coupled to one end of a rod 1 of the first rod, and a second rod 3 is vertically and T-shaped coupled to the other end. Are connected so that the second handle 4 is horizontal and orthogonal to the first rod 1.

【0003】また、該第2のロッド3の他端には回転位
置調節機構5を介して第3のロッド6が設けられ、該第
3のロッド6の他端には角度調節機構7を介して第4の
ロッド8が取り付けられ、さらに該第4のロッド8の他
端には保持具を取り付けるチャック9が設けられてい
る。
A third rod 6 is provided at the other end of the second rod 3 via a rotation position adjusting mechanism 5, and at the other end of the third rod 6 via an angle adjusting mechanism 7. A fourth rod 8 is attached to the second rod 8, and a chuck 9 for attaching a holder is provided at the other end of the fourth rod 8.

【0004】そして角度調節機構7は図5に示すように
第3のロッド6と第4のロッド8の一端に軸10が挿通
され、該軸10は第4のロッド8に固定されている。ま
た該軸10は一端にねじ部11を有し軸部に(b)図の
如く2面10a,10bが形成されている。そして該2
面部に嵌合する2面を有するカラー12が該軸10に嵌
合され、更に該カラー12を押圧するナットハンドル1
3が螺合されている。
As shown in FIG. 5, a shaft 10 is inserted into one end of a third rod 6 and a fourth rod 8 of the angle adjusting mechanism 7, and the shaft 10 is fixed to the fourth rod 8. The shaft 10 has a screw portion 11 at one end, and two surfaces 10a and 10b are formed on the shaft portion as shown in FIG. And the 2
A nut handle 1 that has a collar 12 having two surfaces fitted to the surface portion and is fitted to the shaft 10 and further presses the collar 12
3 is screwed.

【0005】また第3のロッド6とカラー12とが対向
する面には互いに嵌合するセレーション14が形成され
且つばね15が挿入され常時は離反する方向に付勢して
いる。そして、ナットハンドル13を締めつけることに
よりカラー12は矢印A方向に押圧され、そのセレーシ
ョンが第3のロッドのセレーションに嵌合して第3のロ
ッド6と第4のロッド8とを固定するようになってい
る。
On the surface of the third rod 6 and the collar 12 facing each other, serrations 14 are formed to fit each other, and a spring 15 is inserted therein so as to always urge them in the direction away from each other. Then, by tightening the nut handle 13, the collar 12 is pressed in the direction of arrow A, and its serration is fitted to the serration of the third rod to fix the third rod 6 and the fourth rod 8 together. Has become.

【0006】そして、このアジャスタブルカップポジシ
ョナーは図6のようにして使用される。即ち、アジャス
タブルカップポジショナーの角度調節機構7を所定角度
に調整し、チャックに人工股関節用の半球状のカップ1
6を取り付けておき、人工股関節置換手術を受ける被手
術者17をベッド18上に横臥させ、アジャスタブルカ
ップポジショナーの第1のロッド1を水平に保持しなが
ら該アジャスタブルカップポジショナーに予め取り付け
られたカップ16を被手術者17の股関節の臼蓋に装着
するのである。
The adjustable cup positioner is used as shown in FIG. That is, the angle adjustment mechanism 7 of the adjustable cup positioner is adjusted to a predetermined angle, and the hemispherical cup 1 for an artificial hip joint is attached to the chuck.
6, the subject 17 undergoing the hip replacement operation is laid on the bed 18, and the cup 16 previously attached to the adjustable cup positioner while holding the first rod 1 of the adjustable cup positioner horizontally. Is attached to the hip of the subject 17.

【0007】[0007]

【発明が解決しようとする課題】上記人工股関節置換手
術においては、カップ16の装着角度を所定の角度に正
確に合わせる必要がある。ところが、前記アジャスタブ
ルカップポジショナーの角度調節機構7の軸10の2面
10a,10bとカラーの孔の2面との間にはハメアイ
に必要な微小なクリアランスが存在するため、このクリ
アランスにより第3のロッド6と第4のロッド8との間
にガタが生じ、第4のロッド8の先端ではガタが増幅さ
れる。例えば、軸10とカラーの孔との間に0.05m
mのクリアランスがあった場合、軸10から150mm
離れた第4のロッド8の先端では約3mm(角度:1°
9′20″)のずれが発生する。
In the above-described hip replacement surgery, the mounting angle of the cup 16 must be accurately adjusted to a predetermined angle. However, since there is a small clearance required for the eye contact between the two surfaces 10a and 10b of the shaft 10 of the angle adjusting mechanism 7 of the adjustable cup positioner and the two surfaces of the collar hole, the third clearance is generated by this clearance. A play is generated between the rod 6 and the fourth rod 8, and the play is amplified at the tip of the fourth rod 8. For example, 0.05 m between the shaft 10 and the hole of the collar.
If there is clearance of m, 150 mm from axis 10
Approximately 3 mm (angle: 1 °) at the tip of the remote fourth rod 8
9'20 ").

【0008】本発明は上記従来の問題点に鑑み、軸とカ
ラーとの間の回転ガタを防止可能とした回転ガタ防止構
造をを実現することを目的とする。
The present invention has been made in view of the above-mentioned conventional problems, and has as its object to realize a rotation play prevention structure capable of preventing rotation play between a shaft and a collar.

【0009】[0009]

【課題を解決するための手段】本発明の回転ガタ防止構
造は、中心軸に対して平行な2面20a,20bが形成
された軸20と、内面に2面23a,23bが形成され
た孔23を有して前記軸20に遊嵌可能な2個のカラー
21,22とからなり、前記カラー21,22のそれぞ
れ一方の端面を、該カラー21,22の中心軸に直交し
且つ前記2面23a,23bに対して平行な直線を含む
斜面24に形成し、該2個のカラー21,22を斜面2
4同士が対向するようにして軸20に嵌挿し、該2個の
カラー21,22同士を押圧することにより、斜面24
同士を互いに反対方向に滑らせて軸20とカラー21,
22とのガタを取ることを特徴とする。この構成をとる
ことにより、簡単な構成でガタを防止可能とした回転ガ
タ防止構造が得られる。
According to the present invention, there is provided an anti-rotation structure comprising a shaft having two surfaces parallel to a center axis and a hole having two surfaces formed on an inner surface. 23, two collars 21 and 22 that can be loosely fitted to the shaft 20. One end face of each of the collars 21 and 22 is perpendicular to the central axis of the collar 21 and 22 and The two collars 21 and 22 are formed on a slope 24 including a straight line parallel to the surfaces 23a and 23b.
4 are fitted to the shaft 20 so that they face each other, and the two collars 21 and 22 are pressed against each other.
Sliding each other in opposite directions, the shaft 20 and the collar 21,
It is characterized in that the play with 22 is removed. With this configuration, it is possible to obtain a rotation backlash prevention structure that can prevent backlash with a simple configuration.

【0010】[0010]

【発明の実施の形態】図1は本発明の実施の形態を示す
図で、(a)は縦断面図、(b)は(a)図のb−b線
における断面図である。同図において符号20は軸、2
1,22はカラーである。そして軸20は中心軸に平行
に2面20a,20bが形成されている。また、カラー
21,22は中心軸に平行な2面23a,23bを有す
る孔24が形成され、軸20に遊嵌されるようになって
おり、その一方の端面には中心軸に直交し且つ2面23
a,23bに対して平行な直線を含む斜面24が形成さ
れている。このように形成された2つのカラー21,2
2は、図の如く、その斜面24同士を対向させて軸20
に嵌挿されている。
FIG. 1 is a view showing an embodiment of the present invention, in which (a) is a longitudinal sectional view, and (b) is a sectional view taken along line bb of (a). In the figure, reference numeral 20 denotes an axis, 2
Reference numerals 1 and 22 are colors. The shaft 20 has two surfaces 20a and 20b formed parallel to the central axis. The collars 21 and 22 are formed with a hole 24 having two surfaces 23a and 23b parallel to the central axis, so that the collars 24 and 22 are loosely fitted to the shaft 20, and one end surface thereof is orthogonal to the central axis and 2 sides 23
A slope 24 including a straight line parallel to a and 23b is formed. The two collars 21 and 2 thus formed
2 is a shaft 20 with its slopes 24 facing each other as shown in the figure.
It is inserted in.

【0011】このように構成された本実施の形態は、図
2に示すように2つのカラー21,22を互いに接近す
る方向に押圧すると、斜面24同士が滑り、一方のカラ
ー21は矢印A方向に、他方のカラー22は矢印B方向
に移動する。これによりカラー21,22は互いに反対
の面が軸20の2面20a,20bに接触する。従って
軸の2面20a,20bにはそれぞれカラー21,22
の1面が接触し隙間が無くなることになりガタが防止さ
れる。
In this embodiment constructed as described above, when the two collars 21 and 22 are pressed in a direction approaching each other as shown in FIG. 2, the slopes 24 slide, and one collar 21 moves in the direction of arrow A. Then, the other collar 22 moves in the arrow B direction. Thereby, the opposite surfaces of the collars 21 and 22 contact the two surfaces 20a and 20b of the shaft 20. Therefore, the collars 21 and 22 are respectively provided on the two surfaces 20a and 20b of the shaft.
Are contacted to eliminate a gap, thereby preventing backlash.

【0012】なお、本実施の形態では、軸20及びカラ
ー21,22には2面を取るように説明したが、1面の
みでも良い。但しこの場合は回転ガタ防止性能は2面の
場合よりは落ちる。
In this embodiment, the shaft 20 and the collars 21 and 22 have been described as having two surfaces. However, only one surface may be used. However, in this case, the rotation backlash prevention performance is lower than in the case of two surfaces.

【0013】[0013]

【実施例】図3は本発明の実施例を説明するための図で
ある。本実施例は本発明をアジャスタブルカップポジシ
ョナーに用いたものであり、角度調節機構以外は図4で
説明した従来のアジャスタブルカップポジショナーと同
様である。従って角度調節機構以外の説明は省略し、以
下角度調節機構に付いて説明する。
FIG. 3 is a diagram for explaining an embodiment of the present invention. This embodiment uses the present invention for an adjustable cup positioner, and is the same as the conventional adjustable cup positioner described with reference to FIG. 4 except for the angle adjusting mechanism. Therefore, description other than the angle adjusting mechanism is omitted, and the angle adjusting mechanism will be described below.

【0014】図3に示す角度調節機構30は第3のロッ
ド31と第4のロッド32の一端を軸33が挿通され、
該軸33は第4のロッド32に固定されている。また該
軸33は一端にねじ部34を有し軸部に(b)図の如く
2面33a,33bが形成されている。そして該軸33
に嵌合する2面35a,35bが形成された孔35を有
する2個のカラー36,37が該軸33に遊嵌され、更
に該カラー36,37を押圧するナットハンドル38が
ねじ部34に螺合されている。
An angle adjusting mechanism 30 shown in FIG. 3 has a shaft 33 inserted through one end of a third rod 31 and a fourth rod 32.
The shaft 33 is fixed to the fourth rod 32. The shaft 33 has a screw portion 34 at one end, and two surfaces 33a and 33b are formed on the shaft portion as shown in FIG. And the shaft 33
Two collars 36 and 37 having holes 35 formed with two surfaces 35a and 35b are loosely fitted to the shaft 33, and a nut handle 38 for pressing the collars 36 and 37 is attached to the screw portion 34. It is screwed.

【0015】また、前記2個のカラー36,37の対向
する面には、中心軸に直交し且つ2面35a,35bに
対して平行な直線を含む斜面39が形成され、さらに、
第3のロッド31とカラー37とが対向する面には互い
に嵌合するセレーション40が形成され且つばね41が
挿入されている。
An inclined surface 39 including a straight line perpendicular to the central axis and parallel to the two surfaces 35a and 35b is formed on the opposing surfaces of the two collars 36 and 37.
A serration 40 is formed on the surface where the third rod 31 and the collar 37 face each other, and a spring 41 is inserted into the serration 40.

【0016】このように構成された本実施例の作用を次
に説明する。先ず第3のロッド31と第4のロッド32
との角度を所定の角度に調節し、次にナットハンドル3
8を回動しカラー36,37を押圧する。すると、カラ
ー37はばね41の付勢力に抗して第3のロッド31に
当接し、セレーション40同士を嵌合させる。
The operation of the embodiment constructed as described above will now be described. First, a third rod 31 and a fourth rod 32
Is adjusted to a predetermined angle, and then the nut handle 3
8, the collars 36 and 37 are pressed. Then, the collar 37 contacts the third rod 31 against the urging force of the spring 41, and the serrations 40 are fitted together.

【0017】同時に2個のカラー36,37は斜面39
で互いに滑り、一方のカラー36は矢印A方向に、他方
のカラー37は矢印B方向に滑る。これにより軸33の
2面とカラー36,37の孔の2面との間のクリアラン
スを吸収しクリアランスをゼロにしてガタを防止するこ
とができる。
At the same time, the two collars 36 and 37 are inclined 39
, One collar 36 slides in the direction of arrow A and the other collar 37 slides in the direction of arrow B. As a result, the clearance between the two surfaces of the shaft 33 and the two surfaces of the holes of the collars 36 and 37 can be absorbed and the clearance can be made zero to prevent backlash.

【0018】[0018]

【発明の効果】本発明の回転ガタ防止構造によれば、2
面が形成された軸に、2面が形成され且つ一方の端面に
斜面が形成された2個のカラーを斜面同士が対向するよ
うにして前記軸に嵌挿しカラー同士を押圧するようにし
たことにより、精密な精度を要することなく、簡単な構
造で確実に回転ガタを防止することができる。なお本発
明は実施例で説明したアジャスタブルカップポジショナ
ーの他、創外固定具、外固定用ブレース、牽引装具等の
医療用具、さらに一般民生用、産業用等に応用可能であ
る。
According to the rotation play preventing structure of the present invention, 2
The two collars, each having two surfaces formed on the shaft with the surface formed and the slope formed on one end surface, are fitted to the shaft so that the slopes face each other, and the collars are pressed together. Accordingly, it is possible to reliably prevent the rotational play with a simple structure without requiring precise precision. In addition to the adjustable cup positioner described in the embodiments, the present invention can be applied to medical devices such as external fixation devices, external fixation braces, and traction devices, as well as general consumer use, industrial use, and the like.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の実施の形態を示す図で、(a)は縦断
面図、(b)は(a)図のb−b線における断面図であ
る。
FIGS. 1A and 1B are diagrams showing an embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view, and FIG. 1B is a sectional view taken along line bb in FIG.

【図2】本発明の実施の形態の作用を説明するための図
で、(a)は縦断面図、(b)は(a)図のb−b線に
おける断面図である。
FIGS. 2A and 2B are views for explaining the operation of the embodiment of the present invention, in which FIG. 2A is a longitudinal sectional view, and FIG. 2B is a sectional view taken along line bb in FIG.

【図3】本発明の実施例を示す図で、(a)は縦断面
図、(b)は(a)図のb−b線における拡大断面図で
ある。
3A and 3B are diagrams showing an embodiment of the present invention, in which FIG. 3A is a longitudinal sectional view, and FIG. 3B is an enlarged sectional view taken along line bb in FIG. 3A.

【図4】従来のアジャスタブルカップポジショナーを示
す図で、(a)は正面図、(b)は側面図である。
4A and 4B are views showing a conventional adjustable cup positioner, wherein FIG. 4A is a front view and FIG. 4B is a side view.

【図5】従来のアジャスタブルカップポジショナーにお
ける角度調節機構を示す図で、(a)は縦断面図、
(b)は(a)図のb−b線における断面図である。
FIG. 5 is a view showing an angle adjusting mechanism in a conventional adjustable cup positioner, where (a) is a longitudinal sectional view,
(B) is sectional drawing in the bb line of (a) figure.

【図6】従来のアジャスタブルカップポジショナーの使
用状態を示す図である。
FIG. 6 is a diagram showing a use state of a conventional adjustable cup positioner.

【符号の説明】[Explanation of symbols]

20…軸 20a,20b,23a,23b…2面 21,22…カラー 23…孔 24…斜面 30…角度調節機構 31…第3のロッド 32…第4のロッド 33…軸 34…ねじ部 35…孔 36,37…カラー 38…ナットハンドル 39…斜面 40…セレーション 41…ばね Reference numeral 20: shaft 20a, 20b, 23a, 23b: two surfaces 21, 22, collar 23: hole 24, inclined surface 30, angle adjustment mechanism 31, third rod 32, fourth rod 33, shaft 34, screw portion 35, etc. Holes 36 and 37 Collar 38 Nut handle 39 Slope 40 Serration 41 Spring

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 中心軸に対して平行な2面(20a,2
0b)が形成された軸(20)と、内面に2面(23
a,23b)が形成された孔(23)を有して前記軸
(20)に遊嵌可能な2個のカラー(21,22)とか
らなり、 前記カラー(21,22)のそれぞれ一方の端面を、該
カラー(21,22)の中心軸に直交し且つ前記2面
(23a,23b)に対して平行な直線を含む斜面(2
4)に形成し、該2個のカラー(21,22)を斜面
(24)同士が対向するようにして軸(20)に嵌挿
し、該2個のカラー(21,22)同士を押圧すること
により、斜面(24)同士を互いに反対方向に滑らせて
軸(20)とカラー(21,22)とのガタを取ること
を特徴とする回転ガタ防止構造。
1. Two surfaces (20a, 2a) parallel to a central axis.
0b) is formed on the shaft (20), and two surfaces (23) are formed on the inner surface.
a, 23b) are formed of two collars (21, 22) having a hole (23) in which the shaft (20) is loosely fitted, and each of the collars (21, 22) has one of them. The end face is inclined (2) including a straight line perpendicular to the center axis of the collar (21, 22) and parallel to the two faces (23a, 23b).
4), the two collars (21, 22) are fitted to the shaft (20) such that the slopes (24) face each other, and the two collars (21, 22) are pressed together. In this way, the rotation play is prevented by sliding the slopes (24) in directions opposite to each other to remove play between the shaft (20) and the collars (21, 22).
JP14973298A 1998-05-29 1998-05-29 Rotary chattering prevention structure Pending JPH11332894A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14973298A JPH11332894A (en) 1998-05-29 1998-05-29 Rotary chattering prevention structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14973298A JPH11332894A (en) 1998-05-29 1998-05-29 Rotary chattering prevention structure

Publications (1)

Publication Number Publication Date
JPH11332894A true JPH11332894A (en) 1999-12-07

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ID=15481612

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14973298A Pending JPH11332894A (en) 1998-05-29 1998-05-29 Rotary chattering prevention structure

Country Status (1)

Country Link
JP (1) JPH11332894A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011152317A1 (en) * 2010-06-01 2011-12-08 カヤバ工業株式会社 Joining structure, and fluid pressure shock absorber

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011152317A1 (en) * 2010-06-01 2011-12-08 カヤバ工業株式会社 Joining structure, and fluid pressure shock absorber
JP2011252528A (en) * 2010-06-01 2011-12-15 Kyb Co Ltd Connecting structure
US10088007B2 (en) 2010-06-01 2018-10-02 Kyb Corporation Joint structure and hydraulic shock absorber

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