JPS629313A - Polygon mirror - Google Patents

Polygon mirror

Info

Publication number
JPS629313A
JPS629313A JP14889185A JP14889185A JPS629313A JP S629313 A JPS629313 A JP S629313A JP 14889185 A JP14889185 A JP 14889185A JP 14889185 A JP14889185 A JP 14889185A JP S629313 A JPS629313 A JP S629313A
Authority
JP
Japan
Prior art keywords
polygon mirror
peripheral part
mirror
polygon
reduced
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
Application number
JP14889185A
Other languages
Japanese (ja)
Other versions
JPH0431370B2 (en
Inventor
Kazuhiro Kimura
和博 木村
Hiroyuki Ikenaga
池永 博行
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.)
Sharp Corp
Original Assignee
Sharp Corp
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 Sharp Corp filed Critical Sharp Corp
Priority to JP14889185A priority Critical patent/JPS629313A/en
Publication of JPS629313A publication Critical patent/JPS629313A/en
Publication of JPH0431370B2 publication Critical patent/JPH0431370B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00Optical elements other than lenses
    • G02B5/08Mirrors
    • G02B5/09Multifaceted or polygonal mirrors, e.g. polygonal scanning mirrors; Fresnel mirrors

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Elements Other Than Lenses (AREA)
  • Mechanical Optical Scanning Systems (AREA)

Abstract

PURPOSE:To improve productivity and working precision by forming a step so that the outer peripheral part of a polygon mirror is thicker than the inner peripheral part. CONSTITUTION:A groove 12 is formed in the top surface of the polygon mirror 10 and the thickness of its outer peripheral part B is made larger than that of the inner peripheral part; and the rotating shaft of a jig is inserted into a fitting hole 2 and one-flank sides of plural mirrors 10 are finished into specular surfaces by using a diamond cutting tool. Only the plane part of the outer peripheral part B as a contacting surface between stacked mirrors is surface- worked with high precision, so the cumulation of work errors due to the stacking is reduced and deterioration in parallelism due to the entry of dust, etc., to the contact surface is reduced. Thus, the cost is reduced and the quality is improved.

Description

【発明の詳細な説明】 〈産業上の利用分野〉 本発明は新規な構造によって高精度を維持したまま生産
の高能率化を図ったポリゴンミラーに関するものである
DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polygon mirror that achieves high production efficiency while maintaining high precision through a novel structure.

〈従来の技術〉 近年、レーザ光を走査するためのスキャナとして正多角
柱体で構成され、その各側面が鏡面となっている回転多
面鏡(以下ポリゴンミラー)が使用される。例れば第6
図に示す様にレーザプリンタの感光体ドラムに対しレー
ザ光を走査するべくレーザ光発生装置より出射されたレ
ーザ光を高速度(5000〜1500rpm)で回転す
るポリゴンミラー■に照射し、その反射光をレンズユニ
ットを介して感光ドラムに照射すれば、レーザ光は感光
体ドラムの水平方向にスキャンされ高速度の印刷が可能
となる。とのレーザプリンタは従来よシー′般に使用さ
れているラインプリンタ、シリアルプリンタに比べて格
段に速い印字スピードを得ることができる為、又画質や
騒音の点でも優れているので大いに期待を集めているも
のである。このレーザプリンタにおいて極めて重要な・
要素であるのが上記のポリゴンミラーである。ポリゴン
ミラーはその使用目的上、高精度が要求される。そして
その形状及び精度の高さ故に非常に高価な部品となり、
レーザプリンタの低価格化に際し非常なネックとなって
いるのも、このポリゴンミラーであると言える。つまシ
高精度に加工されたポリゴンミラーをいかに安価に提供
できるかが非常な技術的課題となっている。
<Prior Art> In recent years, a rotating polygon mirror (hereinafter referred to as a polygon mirror), which is composed of a regular polygonal column and has mirror surfaces on each side, has been used as a scanner for scanning laser light. For example, the 6th
As shown in the figure, in order to scan the photoreceptor drum of a laser printer with a laser beam, a laser beam emitted from a laser beam generator is irradiated onto a polygon mirror (■) rotating at high speed (5000 to 1500 rpm), and the reflected light is When the laser beam is irradiated onto the photosensitive drum through the lens unit, the laser beam is scanned in the horizontal direction of the photosensitive drum, enabling high-speed printing. Laser printers are attracting great expectations because they can achieve much faster printing speeds than conventional line printers and serial printers, and are also superior in image quality and noise. It is something that This is extremely important for this laser printer.
The element is the polygon mirror mentioned above. Polygon mirrors require high precision due to their intended use. Because of its shape and high precision, it becomes a very expensive part.
It can be said that this polygon mirror is a major bottleneck in lowering the price of laser printers. How to provide polygon mirrors processed with high precision at a low cost is an extremely important technical issue.

従来のポリゴンミラー1の側断面図を第4図に示す。こ
のポリゴンミラー1には該ポリゴンミラー1を高速回転
駆動せしめる駆動モータの取付穴2が設けられ、該取付
穴2を除いては略均−の厚みを備えていた。以上のSを
ポリゴンミラーにおいてその低価格化を実現するために
は生産の高能−率化を図ることが必要である。その一手
段としてポリゴンミラーの最終的な加工である鏡面加工
直前の状態のもの(ブランク)3を複数枚重ね、夏サイ
クルの機械加工による最終仕上げ鏡面加工によシ、一時
に複数枚のポリゴンミラーを得ようとする方法がある。
A side sectional view of a conventional polygon mirror 1 is shown in FIG. This polygon mirror 1 was provided with a mounting hole 2 for a drive motor for driving the polygon mirror 1 to rotate at high speed, and had a substantially uniform thickness except for the mounting hole 2. In order to reduce the cost of polygon mirrors using the above S, it is necessary to improve production efficiency. One way to do this is to stack multiple polygon mirrors (blanks) 3 in the state immediately before mirror polishing, which is the final processing of polygon mirrors, and perform the final mirror polishing by machining in the summer cycle, thereby creating multiple polygon mirrors at once. There is a way to try to get it.

第5図に従来の形状のポリゴンミラーブランクを複数枚
重ねて、鏡面加工を行なっている例を示している。
FIG. 5 shows an example in which a plurality of conventionally shaped polygon mirror blanks are stacked and mirror-finished.

同図において4はポリゴンミラー鏡面加工用治具であシ
、該治具4の円柱状突出部に6個のポリゴンミラーブラ
ンク3がセツティングされる。5はポリゴンミラーブラ
ンク3の押えであシ、6は該押え5に対して押圧力を付
与する押えバネである。7はねじであシ、該ねじ7を上
部よシ回転させながら下降させることで上記押えバネ6
に圧力を印加する。8は単結晶ダイヤモンドバイトであ
り、9は該単結晶ダイヤモンドバイト8との回転バラン
スをとる為のバランスウェイトである。上記単結晶ダイ
ヤモンドバイト8は同図の矢印方向に円を描いて回転運
動を行なう。そして該回転運動を行ないつつ上記積層し
たポリゴンミラーブランク3に接近し、該ポリゴンミラ
ーブランク3の1側面に対し鏡面の切削加工を施こす。
In the figure, reference numeral 4 denotes a jig for polishing a polygon mirror, and six polygon mirror blanks 3 are set on a cylindrical protrusion of the jig 4. 5 is a presser foot for the polygon mirror blank 3, and 6 is a presser spring that applies a pressing force to the presser foot 5. 7 is a screw, and by rotating the screw 7 from the top and lowering it, the presser spring 6 is removed.
Apply pressure to. 8 is a single-crystal diamond cutting tool, and 9 is a balance weight for keeping rotational balance with the single-crystal diamond cutting tool 8. The single-crystal diamond cutting tool 8 rotates in a circular motion in the direction of the arrow in the figure. Then, while performing the rotational movement, the laminated polygon mirror blank 3 is approached, and one side surface of the polygon mirror blank 3 is machined to have a mirror surface.

尚、との際、治具4は上記単結晶ダイヤモンドバイト8
0回転軸に直交する方向に水平移動を行なう。ポリゴン
ミラーブランク3の1側面に対し鏡面の切削加工が完成
した時点で治具4は30度の回転が外され、次の側面に
対する鏡面の切削加工が実行される。
In this case, the jig 4 is the single crystal diamond bit 8 mentioned above.
Performs horizontal movement in the direction perpendicular to the zero rotation axis. When the cutting of the mirror surface on one side of the polygon mirror blank 3 is completed, the jig 4 is rotated by 30 degrees, and the cutting of the mirror surface on the next side is performed.

以上の様な切削加工においてポリゴンミラーの品質を高
精度に維持するためには、上記複数のポリゴンミラーブ
ランク3の重ね合わせの時に互いに接触する各ポリゴン
ミラーブランク3の上下両面を非常に高い精度で平面か
つ互いに平行に加工しておく必要がある。しかし第5図
に示すように、特に上段のポリゴンミラーブランク程、
加工誤差が累積されるが、従来の形状のポリゴンミラー
では・各ポリコンミラーの接触する面積が広いため、接
触面全面を高精度に平面加工及び平行加工することは、
加工技術的に難しく、その為にコストアップの要因とな
っていた。また、鏡面加工を行なうためのポリゴンミラ
ーブランクのセツティングの際の加工室内のチリ・ホコ
リや切削屑等がポリコンミラーブランクの広い接触面間
にかみ込むことによる精度悪化の可能性も高いという問
題点があった。
In order to maintain the quality of polygon mirrors with high precision during the cutting process described above, the upper and lower surfaces of each polygon mirror blank 3 that come into contact with each other when superimposing the plurality of polygon mirror blanks 3 must be cut with very high precision. They must be machined flat and parallel to each other. However, as shown in Figure 5, especially the upper polygon mirror blank,
Processing errors accumulate, but with conventionally shaped polygon mirrors, each polygon mirror has a large contact area, so it is difficult to perform flat and parallel processing on the entire contact surface with high precision.
The processing technology was difficult, which led to an increase in costs. Another problem is that when setting a polygon mirror blank for mirror finishing, there is a high possibility that the accuracy will deteriorate due to dust, cutting chips, etc. in the processing chamber getting caught between the wide contact surfaces of the polygon mirror blank. There was a point.

く目 的〉 本発明は、以上の点に鑑みポリゴンミラーブランクの生
産性と加工精度の両方の条件を充足する構造を提供する
ことを目的とするものである〇〈実施例〉 以下、本発明に係るポリコンミラーの実施例につき図面
を用いて詳細に説明を行なう。
Purpose> In view of the above points, it is an object of the present invention to provide a structure that satisfies both the productivity and processing accuracy requirements for polygon mirror blanks. Embodiments of the polycon mirror will be described in detail with reference to the drawings.

第1図(a)に本発明に係るポリゴンミラーの平面図を
示し、第1図(b)にその側断面図を示す。このポリゴ
ンミラーIOの中心部分には該ポリゴンミラー10を高
速回転駆動せしめる駆動モータに取シ付ける為の取付穴
2が設けられる。11は上記駆動モータにこのポリゴン
ミラーlOを画定する固定用ネジのネジ穴である。12
はポリゴンミラー10の中心を中心として円状に形成さ
れたバランスウェイト取将用溝である。このバランスウ
ェイト取付用溝12は旋盤等にょる溝切シ加工によって
加工できるものである。このバランスウェイト取付用溝
12内部の所定位置にバランスウェイト(接着剤でも構
わない)を接着することによってポリゴンミラーを高速
回転せしめた時にバランスをとることができるものであ
る。上記ポリゴンミラー10は上記バランスウェイト取
付用溝■2を境にして厚みが薄い内周部Aとその厚みが
厚い外周部Bとに分かれる。
FIG. 1(a) shows a plan view of a polygon mirror according to the present invention, and FIG. 1(b) shows a side sectional view thereof. A mounting hole 2 is provided in the center of the polygon mirror IO for mounting a drive motor that drives the polygon mirror 10 in high-speed rotation. Reference numeral 11 denotes a screw hole for a fixing screw that defines the polygon mirror IO to the drive motor. 12
is a balance weight guide groove formed in a circular shape centered on the center of the polygon mirror 10. This balance weight mounting groove 12 can be machined by grooving using a lathe or the like. By bonding a balance weight (adhesive may be used) at a predetermined position inside this balance weight mounting groove 12, it is possible to maintain balance when the polygon mirror is rotated at high speed. The polygon mirror 10 is divided into a thinner inner circumferential portion A and a thicker outer circumferential portion B with the balance weight mounting groove 2 as a boundary.

上記形状のポリゴンミラーの鏡面加工を施こす前のもの
(即ちポリゴンミラーブランク)を第2図に示す如くポ
リゴンミラー鏡面加工用治具4の円柱状突出部に8個だ
けセツティングする。6はポリゴンミラーブランク10
の外周部Bのみを押圧する押工バネであり、7は回転し
ながら下降させることで上記押えバネ6に圧力を印加す
るねじである08は単結晶ダイヤモンドノ(イトであり
、9は該単結晶ダイヤモンドバイト8との回転)くラン
スヲトる為のバランスウェイトである0上記単結晶ダイ
ヤモンドバイト8は同図の矢印方向に円を描いて回転運
動を行なう。上記単結晶ダイヤモンドバイト8は回転運
動を行ないつつ上記積層したポリゴンミラーブランクl
OK接近し、該ポリゴンミラーブランク10の!側面に
対し鏡面の切削加工を施こす。尚、この際治具4は上記
単結晶ダイヤモンドバイト8の回転軸に直交する方向に
水平移動を行なう。ポリゴンミラーブランク10の1側
面に対し鏡面の切削加工が完成した時点で冶具4は30
度の回転がなされ、次の側面に対する鏡面の切削加工が
実行される。
As shown in FIG. 2, eight polygon mirrors having the shape described above before being mirror-finished (that is, polygon mirror blanks) are set on the cylindrical protrusion of the jig 4 for mirror-finishing a polygon mirror. 6 is polygon mirror blank 10
7 is a screw that applies pressure to the presser spring 6 by lowering it while rotating.08 is a single crystal diamond, and 9 is a screw that applies pressure to the presser spring 6. (Rotation with the crystal diamond cutting tool 8) The single crystal diamond cutting tool 8, which is a balance weight for running the rotation, rotates in a circular motion in the direction of the arrow in the figure. The single-crystal diamond cutting tool 8 rotates while rotating the laminated polygon mirror blank l.
OK, approach the polygon mirror blank 10! A mirror-like cutting process is applied to the sides. At this time, the jig 4 is moved horizontally in a direction perpendicular to the rotation axis of the single-crystal diamond cutting tool 8. When the mirror surface cutting process is completed on one side of the polygon mirror blank 10, the jig 4 is
degree rotation and mirror cutting is performed on the next side surface.

ここで上記の形状のポリゴンミラーブランクであれば第
2図に示す様に上下のポリゴンミラーブランク10同志
が接触する範囲が狭いためこの範囲即ち厚みが厚い外周
部Bのみに限定して高精度の平行平面加工を行なえばよ
い。即ちこの平行平面加工についての負担を少なくでき
る。更に、ポリゴンミラー鏡面加工用治具4に対するポ
リゴンミラーブランク10のセツティングの際に加工室
内のチリ・ホコリや切削屑等が上下のポリゴンミラーブ
ランクIOの間に侵入して平行度を脅かす虞れも少なく
できる。尚、複数のポリゴンミラーブランク10は鏡面
切削加工を行なう側面に近い外周部Bにおいて最大厚み
を有し、その外周部Bの部分に押えバネ6よシの圧力が
加わり固定されるので、加工時のビビリ等による鏡面仕
上げ面の品質低下を効果的に防止できる。
If the polygon mirror blank has the above shape, as shown in FIG. Parallel plane processing may be performed. In other words, the burden of parallel plane processing can be reduced. Furthermore, when setting the polygon mirror blank 10 to the polygon mirror mirror finishing jig 4, there is a risk that dust, cutting chips, etc. in the processing chamber may enter between the upper and lower polygon mirror blanks IO and threaten parallelism. You can also do less. It should be noted that the plurality of polygon mirror blanks 10 have the maximum thickness at the outer periphery B near the side surface where the mirror cutting process is performed, and the pressure of the presser spring 6 is applied to the outer periphery B to fix the blanks, so that during processing It is possible to effectively prevent the quality deterioration of the mirror-finished surface due to chatter, etc.

第8図に本発明に係るポリゴンミラーの他の実施例の側
断面図を示す。同図(a)は内周部Aの範囲内にバラン
スウェイト取付用溝12を設けた構造、同図(b)は外
周部Bの範囲内にバランスウェイト取付用溝12を設け
た構造、同図(c)Fi底底面膜段差設けた構造である
。同図の構造は全て鏡面切削加工を行なう側面部近傍の
厚みが最大となシ、多段重ねの際にその部分のみが上下
で接触する構造を有する。
FIG. 8 shows a side sectional view of another embodiment of the polygon mirror according to the present invention. The figure (a) shows a structure in which a balance weight mounting groove 12 is provided within the range of the inner circumference A, and the figure (b) shows a structure in which a balance weight mounting groove 12 is provided within the range of the outer circumference B. Figure (c) shows a structure with a stepped Fi bottom film. All of the structures shown in the figure have a structure in which the thickness near the side surface portion where the mirror cutting process is performed is maximum, and only that portion contacts top and bottom when stacked in multiple stages.

〈発明の効果〉 以上の本発明によれば製造コストの低減化及び品質の向
上の両面の充実を図ることが可能である0
<Effects of the Invention> According to the present invention described above, it is possible to achieve both reduction in manufacturing costs and improvement in quality.

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

第1図(a)は本発明に係るポリゴンミラーの一実施例
の平面図、第1図(b)はその側断面図、第2図は切削
加工装置の説明図、第3図は本発明に係るポリゴンミラ
ーの他の実施例の側断面図1.第4図は従来のポリゴン
ミラーの側断面図、第5図は切削加工装置の説明図、第
6図はレーザプリンタの内部構造の説明図を示す。 図中、2:取付穴 6:押えバネ 7:ねじ8:単結晶
ダイヤモンドバイト 9:バランスウェイト IO=ポリゴンミラーブランク !I:ネジ穴 12:バランスウェイト取付用溝 代理人 弁理士 福 士 愛 彦(他2名)(a) 冨1図 (a)                −第4図 第5図 第6図
FIG. 1(a) is a plan view of an embodiment of the polygon mirror according to the present invention, FIG. 1(b) is a side sectional view thereof, FIG. 2 is an explanatory diagram of the cutting device, and FIG. 3 is the present invention. 1. Side sectional view of another embodiment of the polygon mirror according to 1. FIG. 4 is a side sectional view of a conventional polygon mirror, FIG. 5 is an explanatory diagram of a cutting device, and FIG. 6 is an explanatory diagram of the internal structure of a laser printer. In the diagram, 2: Mounting hole 6: Presser spring 7: Screw 8: Single crystal diamond bit 9: Balance weight IO = polygon mirror blank! I: Screw hole 12: Balance weight mounting groove Agent Patent attorney Aihiko Fukushi (and 2 others) (a) Figure 1 (a) - Figure 4 Figure 5 Figure 6

Claims (1)

【特許請求の範囲】[Claims] 1、側面部に複数の鏡面を有するポリゴンミラーにおい
て、該ポリゴンミラーの前記側面部に近い部分を回転中
心に近い部分に比して厚くなるように段差を設けたこと
を特徴とするポリゴンミラー。
1. A polygon mirror having a plurality of mirror surfaces on a side surface, characterized in that a step is provided so that a portion of the polygon mirror near the side surface is thicker than a portion near the center of rotation.
JP14889185A 1985-07-05 1985-07-05 Polygon mirror Granted JPS629313A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14889185A JPS629313A (en) 1985-07-05 1985-07-05 Polygon mirror

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14889185A JPS629313A (en) 1985-07-05 1985-07-05 Polygon mirror

Publications (2)

Publication Number Publication Date
JPS629313A true JPS629313A (en) 1987-01-17
JPH0431370B2 JPH0431370B2 (en) 1992-05-26

Family

ID=15463006

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14889185A Granted JPS629313A (en) 1985-07-05 1985-07-05 Polygon mirror

Country Status (1)

Country Link
JP (1) JPS629313A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0157715U (en) * 1987-10-06 1989-04-11
US4820005A (en) * 1986-12-27 1989-04-11 Ricoh Company, Ltd. Method of fixing a polygon mirror and an optical deflector having such polygon mirror
US4892372A (en) * 1984-08-31 1990-01-09 Canon Kabushiki Kaisha Rotating polygon mirror
JPH0216521A (en) * 1988-07-05 1990-01-19 Canon Inc Deflector
JPH0287214U (en) * 1988-12-23 1990-07-10
JPH04190315A (en) * 1990-11-26 1992-07-08 Copal Electron Co Ltd Polygon mirror
JP2009300885A (en) * 2008-06-16 2009-12-24 Canon Inc Optical deflector, optical scanner and image forming apparatus

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60110822U (en) * 1983-12-28 1985-07-27 キヤノン株式会社 polygon mirror

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60110822U (en) * 1983-12-28 1985-07-27 キヤノン株式会社 polygon mirror

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4892372A (en) * 1984-08-31 1990-01-09 Canon Kabushiki Kaisha Rotating polygon mirror
US4820005A (en) * 1986-12-27 1989-04-11 Ricoh Company, Ltd. Method of fixing a polygon mirror and an optical deflector having such polygon mirror
JPH0157715U (en) * 1987-10-06 1989-04-11
JPH0637379Y2 (en) * 1987-10-06 1994-09-28 富士ゼロックス株式会社 Optical deflector
JPH0216521A (en) * 1988-07-05 1990-01-19 Canon Inc Deflector
JPH0287214U (en) * 1988-12-23 1990-07-10
JPH04190315A (en) * 1990-11-26 1992-07-08 Copal Electron Co Ltd Polygon mirror
JP2009300885A (en) * 2008-06-16 2009-12-24 Canon Inc Optical deflector, optical scanner and image forming apparatus

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