JPS58186771A - Fixation device - Google Patents

Abstract

PURPOSE:To prevent oil contamination of transfer paper even if oil adheres to the tip of a pawl member, by providing an auxiliary pawl for turning and displacing its position as transfer paper advances. CONSTITUTION:The tip of transfer paper 6 heated and fixed by a pair of fixation rolls 4 is caught into the side of a pair of paper discharge rolls 8, running along the lower face of a peel-off pawl 11. In this state, a tip 17a of an auxiliary pawl 17 is in the first position state which is shunted, therefore, such a carrying trouble as the tip of the transfer paper 6 is caught by the tip 17a does not occur. When the tip of the transfer paper 6 reaches a step in which it is held by a pair of the rolls 8, pressure in the upper direction operates on a rear end 17b of the auxiliary pawl 17 and it is turned and displaced. Subsequently, its tip 17a takes the second position for advancing to the side of a carrying path 16 from the peel-off pawl 11, by which the transfer paper is guided so as to be separated from the peel-off pawl 11 forcibly even in case of a carrying state of the rear end of the transfer paper 6 is apt to be curled upwards, therefore, the rear end of the transfer paper contacts in the vicinity of the tip of the peel- off pawl 11, and its adhering oil 13a does not adhere to it.

Description

【発明の詳細な説明】 本発明は、定着装置に関するものである。[Detailed description of the invention] The present invention relates to a fixing device.

一般に、定着装置としては第１図に示すように、ヒータ
（１）が内蔵された加熱ローラ（２）と加圧ローラ（３
）とを対向接触させてなる定着ローラ対（４）を設け、
トナー像（５）を有する転写紙（６）を通紙させて加熱
定着させる方式のものが多い。そして、定着ローラ対（
４）を通過した転写紙（６）はガイド板（７）を介して
排紙ローラ対（８）により排紙される。ここで、定着済
みの転写紙（６）先端が加熱ローラ（２）から剥離され
ず巻付くこともあるので、強制的に剥離するよう先端が
加熱ローラ（２）に接触するようばね（９）により付勢
されつつ軸０１に対して回動自在な剥離爪α力が設けら
れている。また、オフセット防止等のためにオイルパン
０′４に収容されたシリコーンオイル等のオイルα］を
塗布フェルトα→により汲み上げ加熱ローラ（２）上に
塗布するオイル塗布装置（ト）も４常は設けられている
。Generally, a fixing device consists of a heating roller (2) with a built-in heater (1) and a pressure roller (3), as shown in FIG.
) are provided in opposing contact with each other.
There are many systems in which a transfer paper (6) carrying a toner image (5) is passed through and fixed by heating. Then, the fixing roller pair (
The transfer paper (6) that has passed through the transfer roller 4) is discharged by a pair of paper discharge rollers (8) via a guide plate (7). At this point, the leading edge of the fixed transfer paper (6) may not be peeled off from the heating roller (2) but may become wrapped around it, so the spring (9) is used so that the leading edge contacts the heating roller (2) to forcefully peel it off. A peeling claw α force is provided which is biased by and rotatable with respect to the shaft 01. In addition, an oil applicator (g) that pumps up oil α such as silicone oil stored in the oil pan 0'4 with a coating felt α and applies it onto the heating roller (2) to prevent offset etc. is also installed. It is provided.

ところが、剥離爪α■の先端が加熱ローラ（２）に接触
しているため、この加熱ローラ（２）上に塗布されたオ
イル（至）が剥離爪α珍先端により掻き取られその下面
に付着オイル（ｔａａ）を生ずる一方において、転写紙
（６）の後端が定着ローラ対（４）から剥離爪α■・ガ
イド板（７）間の搬送路（２）に出たフリー状態では加
熱ローラ（２）による熱の影響で一点鎖線で示すように
上方、すなわち、剥離爪αη側にカールし易く、よって
その後端に付着オイル（ｌａａ）が付着して汚れてしま
うものである。However, since the tip of the peeling claw α■ is in contact with the heating roller (2), the oil coated on the heating roller (2) is scraped off by the tip of the peeling claw α■ and adheres to its lower surface. On the other hand, in the free state where the rear end of the transfer paper (6) has come out from the fixing roller pair (4) to the conveyance path (2) between the peeling claw α■ and the guide plate (7), the heating roller Due to the influence of heat caused by (2), it tends to curl upward, that is, toward the peeling claw αη side, as shown by the dashed line, and therefore, the attached oil (laa) adheres to the rear end and becomes dirty.

本発明は、このような点に鑑みなされたもので、剥離の
ための爪部材に付着したオイルによる転写紙汚れをなく
すことができる定着装置を得ることを目的とするもので
ある。The present invention has been made in view of these points, and an object of the present invention is to provide a fixing device that can eliminate stains on transfer paper due to oil adhering to a peeling claw member.

本発明は、先端が搬送路に対し爪部材よシも退避した第
一位置にて回動自在に支持されつつ転写紙の進行による
後端に対する抑圧によシ先端が搬送路側に進出した第二
位置をとるよう変位する補助爪を設けることにより、爪
部材先端にオイ／ｌｚが付着していても転写紙が強制的
に補助爪によって爪部材から離反した状態に維持される
ので、オイル汚れを生ずることがないように構成したも
のである。The present invention provides a second position in which the leading edge is rotatably supported at a first position where the claw member is also retracted from the conveying path, and the leading edge advances toward the conveying path by pressing the trailing edge as the transfer paper advances. By providing an auxiliary pawl that moves to take the correct position, even if oil/lz adheres to the tip of the pawl, the transfer paper is forcibly maintained in a state separated from the pawl by the auxiliary pawl, thereby eliminating oil stains. The structure is designed to prevent this from occurring.

本発明の一実施例を第２図および第３図に基づいて説明
する。第１図で示した部分と同一部分は同一符号を用い
説明も省略する。本実施例は、剥離爪αηの軸αＱに対
し回動自在に支持されつつ搬送路α６に沿って先端（１
７ｃＬ）および後端（１７−Ｍ）を有する補助爪αηを
設けたものである。ここで、この補助爪り７）は通常状
態においてはストッパーＭにょシ規制されつっばね（至
）により引っ張られてその先端（１７α）が剥離爪Ｏｕ
］も搬送路αＱに対し退避した第一位置（第２図参照）
をとるように設定されている。An embodiment of the present invention will be described based on FIGS. 2 and 3. Components that are the same as those shown in FIG. 1 are designated by the same reference numerals, and description thereof will be omitted. In this embodiment, the tip (1
7cL) and a rear end (17-M). Here, in the normal state, this auxiliary claw 7) is regulated by the stopper M and is pulled by the spring (to) so that its tip (17α) becomes the peeling claw O.
] is also in the first position evacuated from the conveyance path αQ (see Figure 2)
It is set to take .

このとき、後端（１７旬は排紙ローラ対（８）前段にて
搬送路ａＱ中に進出した状態にあるように設定されてい
る。また、前記ばね（至）の引っ張シカは左程強いもの
でなく、第３図に示すように搬送路αＱ中に進出してい
た後端（１７旬が転写紙（６）の進行による抑圧を受け
たとき先端（１７ａ）が剥離爪α■よすも搬１１Ｑに対
して進出した第二位置に変位するように設定されている
。At this time, the rear end (the 17th stage is set to advance into the transport path aQ at the front stage of the paper ejection roller pair (8). Also, the tension of the spring (end) is stronger as the left side However, as shown in Figure 3, when the rear end (17) that had advanced into the conveyance path αQ was suppressed by the advancement of the transfer paper (6), the tip (17a) was removed by the peeling claw α It is also set to be displaced to the second position advanced relative to the carrier 11Q.

なお、加熱ローラ（２）はヒータ（１）にょシ加熱され
てその表面温度が一定に保たれておｐｌまた、加圧ロー
ラ（３）は表面層が弾性体で形成されてこの加熱ローラ
（２）に加圧接触している。Note that the heating roller (2) is heated by the heater (1) to keep its surface temperature constant.The pressure roller (3) has a surface layer made of an elastic material and is heated by the heater (1) to keep its surface temperature constant. 2) is in pressure contact with.

このような構成において、定着ローラ対（４）にょ９加
熱定着された転写紙（６）の先端は上方へカールし易い
ため、剥離爪α役の下面に沿いっつ排紙ローラ対（８）
側にくわえ込まれる。その途中の動作を示すのが、第２
図であり、この状態では補助爪α力の先端（１７ｔＬ）
が退避した第一位置状態にあるので、転写紙（６）先端
が先端（１７α）に引っ掛かる等の搬送トラブルは生じ
ない。しかして、転写紙（６）の先端が排紙ローラ対（
８）に把持される段階まで至ると、この転写紙（６）の
進行に伴ない補助爪Ｃ１７）の後端（１７＋）に上方へ
の押圧力が作用し、補助爪α力は第３図に示すように回
動変位する。すなわち、その先端（１７ｍ）が剥離爪α
ηよシも搬送路ａＱ側に進出する第二位置をとることと
なシ、この状態は転写紙（６）の後端がこの後端（１７
４）を通過し終るまで継続される。したがって、第３図
に一点鎖線で示すように定着ローラ対（４）を通過し終
如搬送路（２）内でフリーとなって上方にカールし易い
転写紙（６）の後端の搬送状態にあっても、進出した補
助爪ａ′ｈの先端（１７ｃＬ）により強制的に剥離爪α
蓼から離反するようにガイドされるので、転写紙（６）
の後端が剥離爪０］）の先端付近に接触しその付着オイ
ル（ｌａａ）が付着するというようなことがなくなる。In such a configuration, since the leading edge of the transfer paper (6) that has been heated and fixed by the pair of fixing rollers (4) tends to curl upward, the pair of paper ejection rollers (8)
Caught in the side. The second part shows the operation during the process.
In this state, the tip of the auxiliary claw α force (17tL)
Since the transfer paper (6) is in the retracted first position, there will be no conveyance trouble such as the leading edge of the transfer paper (6) being caught by the leading edge (17α). Therefore, the leading edge of the transfer paper (6) is connected to the paper ejection roller pair (
8), as the transfer paper (6) advances, an upward pressing force acts on the rear end (17+) of the auxiliary claw C17), and the auxiliary claw α force is as shown in Fig. 3. It is rotated and displaced as shown in . In other words, its tip (17 m) is the peeling claw α
In this state, the rear end of the transfer paper (6) is in the second position where it advances to the conveyance path aQ side.
4) is continued until the end. Therefore, as shown by the dashed line in FIG. 3, the rear end of the transfer paper (6) passes through the pair of fixing rollers (4), becomes free in the conveyance path (2), and tends to curl upward. Even if the separation claw α
The transfer paper (6) will be guided away from the tent.
There is no possibility that the rear end of the peeling claw 0) comes into contact with the vicinity of the tip of the peeling claw 0]) and that the attached oil (laa) is deposited thereon.

よって、転写紙（６）後端のオイル汚れが防止される。Therefore, oil stains on the rear end of the transfer paper (6) are prevented.

なお、この実施例でばねα場、したがって外部からの強
制力によｐ補助爪α力を第一位置に維持させているが、
補助爪αηの自重によシ第−位置が確保されるようにし
てもよい。また、補助爪αηの回動中心もこの実施例の
ように軸（ト）として剥離爪αυと共通化するものに限
らず、その近傍に独立した軸を設゛ける等の方式であっ
てもよい。In this embodiment, the p auxiliary claw α force is maintained at the first position by the spring α field, and therefore by the external force.
The second position may be secured by the weight of the auxiliary claw αη. Furthermore, the center of rotation of the auxiliary claw αη is not limited to the one in which the axis (g) is shared with the peeling claw αυ as in this embodiment, but it is also possible to use a method such as providing an independent axis in the vicinity thereof. good.

本発明は、上述したように回動自在に支持されて先端が
搬送路に対し爪部材よりも退避した第一位置をとシつつ
、転写紙の進行にょる後端に対する抑圧により先端が逆
に搬送路側に進出し九塾二位置をと夛うるよう変位する
補助爪を設けたので、定着ローラ対を通過し終ったフリ
ー状態の転写紙後端が爪部材に接触しようとしても進出
した補助爪先端により離反状態に維持され、よって爪部
材先端に付着したオイルが転写紙後端に付着する等のオ
イル汚れを確実に防止することができ、良質のコピーを
得ることができるものである。As described above, the present invention maintains the first position where the leading end is rotatably supported and retracted from the claw member with respect to the conveyance path, and the leading end is reversed by the pressure against the trailing end as the transfer paper advances. Since we have provided an auxiliary pawl that advances toward the conveyance path side and is displaced over multiple positions, even if the trailing edge of the free transfer paper that has passed through the pair of fixing rollers tries to contact the pawl member, the auxiliary pawl that has advanced will not be affected. The tip is maintained in a separated state, and therefore, it is possible to reliably prevent oil stains such as oil adhering to the tip of the claw member from adhering to the rear end of the transfer paper, and it is possible to obtain high-quality copies.

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

第１図は従来例を示す側面図、第２図は本発明の一実施
例を示す第一位置状態の側面図、第３図はその第二位置
状態を示す側面図でおる。 ２・・・加熱ローラ（定着ローラ）、３・・・加圧ロー
ラ（定着ローラ）、４・・・定着ローラ対、５・・・ト
ナー像、６・・・転写紙、１１・・・剥離爪（爪部材）
、１３・・・オイル、１５・・・オイル塗布装置、１６
・・・搬送路、１７・・・補助爪、１７１１・・・先端
、１７ｋ・・・後端出　願　人　　　株式会社リコーFIG. 1 is a side view showing a conventional example, FIG. 2 is a side view showing an embodiment of the present invention in a first position, and FIG. 3 is a side view showing the second position. 2... Heat roller (fixing roller), 3... Pressure roller (fixing roller), 4... Fixing roller pair, 5... Toner image, 6... Transfer paper, 11... Peeling Claw (claw member)
, 13... Oil, 15... Oil applicator, 16
...Conveyance path, 17...Auxiliary claw, 1711...Tip, 17k...Rear end Applicant Ricoh Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 転写紙上のトナー像を加熱定着する定着ローラ対と、ト
ナー像に接する一方の定着ローラに先端が接触してその
定着ローラから転写紙を剥離させる爪部材と、この定着
ローラ上にオイルを塗布するオイル塗布装置とを備えた
定着装置において、前記定着ローラ対後段の搬送路に沿
って先・後端を有しこの先端が搬送路に対し前記爪部材
よりも退避した第一位置にて回動自在に支持されつつ前
記転写紙の進行による前記後端に対する押圧によシ変位
して前記先端が搬送路に対し前記爪部材よシも進出した
第二位置をとる補助爪を設けたことを特徴とする定着装
置。A pair of fixing rollers that heat and fix the toner image on the transfer paper, a claw member whose tip comes into contact with one of the fixing rollers in contact with the toner image and peels the transfer paper from the fixing roller, and a nail member that applies oil on the fixing roller. In the fixing device, the fixing roller has a leading end and a trailing end along a conveying path after the fixing roller pair, and the leading end rotates at a first position retracted from the pawl member with respect to the conveying path. An auxiliary claw is provided that is freely supported and is displaced by pressure on the rear end as the transfer paper advances, so that the leading end assumes a second position in which the claw member also advances toward the conveyance path. Fixing device.