JP3650702B2

JP3650702B2 - Paper feeder

Info

Publication number: JP3650702B2
Application number: JP21595798A
Authority: JP
Inventors: 哲荒明
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 1998-07-30
Filing date: 1998-07-30
Publication date: 2005-05-25
Anticipated expiration: 2018-07-30
Also published as: JP2000044066A

Description

【０００１】
【発明の属する技術分野】
本発明は、例えばレーザプリンタ、ファクシミリ、複写機等の画像形成装置に備えられる給紙装置、特に２つのシート収容部を並列に配置した所謂タンデムタイプの給紙装置に関するものである。
【０００２】
【従来の技術】
例えば画像形成装置の作像部へ記録シートを自動的に給紙するための給紙手段として、数十〜数千枚の記録シートの収容を可能とした給紙装置が従来から知られている。このような給紙装置では各種サイズの給紙シートに対応できるようになっているのが一般的であり、収容可能な最大サイズ以外の給紙シートを一束に積み上げて収容する場合には必然的にデッドスペースを形成することとなる。そこで、収容可能な最大サイズの半分以下のサイズの給紙シートに関しては、２つのシート収容部を並列に配置し、作像部への給紙のための第１シート収容部に収められたシートがなくなると自動的に第２シート収容部（補助収容部）に収容されているシートを第１シート収容部へ移して連続的な給紙を可能とするような、通常の一束収容シートの２倍の枚数を積載可能としたタンデムタイプの給紙装置が提案された。特に例えば特開平５−２２１５３６号公報では、２つのシート収容部のうちのメイン収容部の記録シートを給紙している間に補助収容部に記録シートを補給可能としてコピー生産性の向上を図った大量給紙装置が提案されている。
【０００３】
このようなタンデムタイプの給紙装置におけるシートの移送にあたっては、第２シート収容部のシート束の移送に伴って第１シート収容部の用紙後端を位置決めするバックフェンスを前方へ倒すようにした構成のものもある（例えば特開平３−２２３０３１号公報や特開平４−２８６３４号公報に開示された構成）が、このようなものでは構造上、空となった第２シート収容部に直ちにシート補充を行うことができないため、多くの装置では移送部材を移送動作終了後にホームポジションまで戻すようにした構成が採用されている。
【０００４】
このような構成では、シート移送に際して、第１シート収容部の底板下降、移送部材によるシート移送、移送完了後の移送部材のホームポジションまでの逆送、第１シート収容部の底板上昇、給紙スタートという順番を経ることとなり、ユーザーにとってはこの一連動作時間が待ち時間となる。
【０００５】
一般的に、数種類の用紙サイズに対応可能なように、第１シート収容部の底板のシート移送方向での長さは積載可能な用紙の最大サイズに合わせられているが、通紙サイズによってはシート移送の際に移送部材が第１シート収容部の底板の稼動領域まで及ぶ場合があり、このような状況を想定すると、シート移送を完了した後にも直ちに底板を上昇させることができない。そこで通常は移送部材がホームポジションまで戻ってきた後に底板の上昇を開始させているが、移送部材が底板の稼動領域から待避すればたとえホームポジションに戻っていなくとも底板を上昇させることが可能であり、言い換えれば待ち時間の短縮を図ることが可能である。
【０００６】
【発明が解決しようとする課題】
そこで本発明者は上記のような待ち時間を短くするために、シート移送が完了して移送部材がホームポジション方向へ待避して所定状態になったならば、当該状態を底板上昇のトリガーに用いることを先に提案した。一つの態様として、移送部材が底板の稼動領域から待避したことを検知するセンサを追加的に設置し、当該センサによる検知のタイミングをトリガーにして底板上昇を開始する構成を開示する。
【０００７】
しかしながら、このような構成では、上記待避検知センサでも移送完了センサでもホームポジションセンサでも、即ち、いずれのセンサでも上記移送部材を検知できない間は移送完了と移送中の区別がつかない。そのため、移送中に機械本体の電源が何らかの事情でオフ、オンされると、リカバリー動作として通常は移送動作を継続するように移送モータを駆動させるようになっているが、検知のための構成によっては実際に移送完了位置に完全に到達している段階がセンサ検知の後である場合があり、そのような場合にはモータストップ信号がいつまでたってもでないこととなり、移送駆動手段の破損とか、サービスマンコールの発生といった問題が生じてしまう。
【０００８】
そこで本発明は、上述の問題に鑑み、移送部材の駆動中に機械本体の電源をオフオンされても当該移送部材の停止位置にかかわらず電源オン後に確実にリカバリー可能で、しかもユーザーの待ち時間を無用に長くすることのない給紙装置を提供することを課題とする。
【０００９】
【課題を解決するための手段】
上記課題は、複数枚の用紙を積載する第１用紙収容部と、当該第１用紙収容部の用紙を給紙位置まで上昇させる昇降手段と、上記第１用紙収容部に対し並列配置された第２用紙収容部と、当該第２用紙収容部の用紙を第１用紙収容部へ一括して移送する移送部材と、当該移送部材がホーム位置にあることを検知する第１検知手段と、上記移送部材が移送完了位置にあることを検知する第２検知手段と、上記移送部材を駆動する駆動手段とを備える給紙装置において、第２用紙収容部側の用紙を第１用紙収容部へ移送する際に電源がオフオンされた場合、移送完了位置にある移送部材が確実に第２検知手段よりも上流側に移動するのに要する時間が経過するまで又は上記第１検知手段が移送部材を検知するまで、上記駆動手段を逆転して移送部材を逆送させ、しかる後に移送動作を再開するように制御することによって解決される。
【００１０】
また、複数枚の用紙を積載する第１用紙収容部と、当該第１用紙収容部の用紙を給紙位置まで上昇させる昇降手段と、上記第１用紙収容部に対し並列配置された第２用紙収容部と、当該第２用紙収容部の用紙を第１用紙収容部へ一括して移送する移送部材と、当該移送部材がホーム位置にあることを検知する第１検知手段と、上記移送部材が移送完了位置にあることを検知する第２検知手段と、上記移送部材を駆動する駆動手段とを備え、移送完了位置にある移送部材が第１用紙収容部に積載されている用紙の上昇を妨げる位置関係を有する給紙装置において、第２用紙収容部側の用紙を第１用紙収容部へ移送終了後に移送部材がホーム位置方向へ退避したことを検知するための第３検知手段を上記第２検知手段で兼用し、当該検知手段での退避検知を給紙位置への用紙上昇トリガーに用いるように構成し、第２用紙収容部側の用紙を第１用紙収容部へ移送する際に電源がオフオンされた場合に、移送完了位置にある移送部材が確実に第２検知手段よりも上流側に移動するのに要する時間が経過するまで又は上記第１検知手段が移送部材を検知するまで、上記駆動手段を逆転して移送部材を逆送させ、しかる後に移送動作を再開するように制御すること、あるいは第１用紙収容部の用紙の有無を検知する手段を設け、第２用紙収容部の用紙を第１用紙収容部へ移送する動作時に、上記第２検知手段が移送完了を検知した後に始めて用紙有りを検知できる位置に、上記用紙有無検知手段を配置したことによっても上記課題を解決できる。
【００１１】
上記第１用紙収容部と上記第２用紙収容部のそれぞれに用紙の有無を検知する手段を備え、両方の用紙有無検知手段の用紙移送方向の間隔が積載可能な最大用紙サイズの最長送り長さよりも大きくとられていれば、一層効果的である。
【００１２】
【発明の実施の形態】
本発明の詳細を、図に示す例に基づいて説明する。
図１に本発明に係る給紙装置を用いた画像形成装置を断面的に示し、図２には第１用紙収容部（以下「右トレイ」という）１の上昇機構を概略斜視図的に示し、図３には第２用紙収容部（以下「左トレイ」という）２からの移送機構を概略斜視図的に示す。
【００１３】
図２に示すように、右トレイの底板６はワイヤで吊られていて、昇降モータ５の駆動によって当該ワイヤを巻き取りあるいは巻き出して底板６を昇降動させるようになっている。右トレイ１に積載された用紙Ｐは図１に示されるように給紙手段３によって１枚ずつ画像形成部４に給紙される。右トレイ１に積載された用紙Ｐがなくなると、昇降モータ５が逆転して底板６が下限センサ７で検知されるまで下降する。下限センサ７が底板６を検知するや、図３で示すように、左トレイ２側の移送モータ８が正転して移送フェンス９が右トレイ側に移動し、左トレイに積載されている用紙Ｐを右トレイの底板上へ移送する。押し付けセンサ１０でその移送の完了が検知されると、移送モータ８の正転が終了する。
【００１４】
押し付けセンサ１０を遮蔽するための移送フェンス９に取り付けられた部片１２を、図５に示すように、スリット部１３と遮蔽部１４とで構成し、スリット部１３の前方に位置する遮蔽部１４の長さを、移送フェンスの移送と底板の上昇がオーバーラップする時間に対応する長さよりも長くとる。そして押し付けセンサ１０の移送完了検知は遮蔽部１４による遮蔽後に押し付けセンサ１０がスリット部１３を認識した時点とし、底板上昇は移送フェンスの逆送時に遮蔽部１４の後端（シート移送の際の先端）通過を押し付けセンサ１０が検知することをトリガーとして上昇開始を行う。この一連の動作をタンデム移送動作と称する。タンデム移送動作を図４にフローチャートで示す。
【００１５】
しかしながら、上記のような構成だけでは、機械本体の電源が一旦オフされ、その時点で移送フェンス９が図５の（１）に示す位置か、（２）に示す位置をとっている場合、いずれに移送フェンスが位置しているかを識別することができない。
【００１６】
本発明においては、移送中の機械本体の電源オン・オフ時に、一定時間、例えば遮蔽部１４の長さ分を移送フェンスが移動する時間＋αか、ホームセンサ１１が移送フェンス９を検知するまで、移送モータ８を逆転させて当該移送フェンス９を逆送させるように制御する。こうすることで移送フェンス９を確実に押し付けセンサ１０よりも上流側に位置させ（図５ ( １ ) に示す位置）、しかる後に移送モータ８を正転させてタンデム移送動作を継続する。この制御動作を図６にフローチャートで示す。
【００１７】
レイアウト的に制約がないならば、右トレイ１の紙有り検知手段１６（図２）を、遮蔽部１４が押し付けセンサ１０を通過してから用紙の送り方向先端が検知されるような位置（図７の領域Ｃ）に配置させる。このような配置によって、移送中の電源オフ・オン時に、右トレイ１の紙有り検知手段１６を基に移送フェンス９の位置を判断して正確なリカバリーを行うことが保証される。この場合の制御動作を図８にフローチャートで示す。
【００１８】
左トレイ２の紙有り検知手段１５（図３）と右トレイ１の紙有り検知手段１６の間隔を積載可能な最大用紙サイズの送り方向長さよりも長くなるように各紙有り検知手段１５，１６を配置し、通常タンデム移送動作では両方の紙有り検知手段１５，１６が同時にオンしない関係をもたせるようにするのが良い。そのような配置関係をもたせることにより、移送中に図５ ( ２ ) に示す位置に移送フェンス９が位置しているときに機械本体の電源がオフされ、機械本体からトレイが引き出されて移送フェンス９の（図１での）左側に用紙を積載されるようなことがあっても、移送フェンス９がホームポジションになく（即ち、ホームセンサ１１がオフ）且つ紙有り検知手段１５，１６が同時にオンすることになるので、用紙積載不良のメッセージを操作部に表示するなどしてユーザーに再セットを促すことができる。
【００１９】
【発明の効果】
請求項１又は２に記載の発明によれば、第２用紙収容部側の用紙を第１用紙収容部へ移送する際に電源がオフオンされた場合、移送完了位置にある移送部材が確実に第２検知手段よりも上流側に移動するのに要する時間が経過するまで又はホームセンサが移送部材を検知するまで、移送用駆動手段を逆転して移送部材を逆送させ、しかる後に移送動作を再開するようになっているので、サービルマンコールを発生させたり、移送用駆動手段を破損するような事態を回避することができる。
【００２０】
請求項３に記載の発明でも、第１用紙収容部の用紙の有無を検知する手段を設け、第２用紙収容部の用紙を第１用紙収容部へ移送する動作時に、上記第２検知手段が移送完了を検知した後に始めて用紙有りを検知できる位置に、上記用紙有無検知手段を配置したので、移送部材の位置が正確に把握でき、サービスマンコールの発生や移送用駆動手段の発生といった事態を回避することができる。
【００２１】
請求項４に記載の発明によれば、２つの用紙有無検知手段の用紙送り方向の間隔が積載可能な最大用紙サイズの最長送り長さよりも大きくなっているので、移送動作中に機械本体の電源オフされ、機械本体から給紙トレイが引き出され、移送部材の左側に誤って用紙を積載されても、移送部材がホーム位置になく且つ両検知手段で紙有り検知が同時にオンすることとなって、この条件に基づいて用紙積載不良のメッセージを操作部に表示するなどしてユーザーに再セットを促すことができ、サービスマンコールの発生や移送用駆動手段の発生といった事態を回避することができる。
【図面の簡単な説明】
【図１】本発明に係る給紙装置を含む画像形成装置の概略断面図である。
【図２】図１に示された給紙装置の第１用紙収容部たる右トレイの上昇機構の斜視図である。
【図３】図１に示された給紙装置の第２用紙収容部たる左トレイの移送機構の概略斜視図である。
【図４】図１に示された給紙装置での移送動作における基本動作を示すフローチャートである。
【図５】移送動作中における押し付けセンサ、ホームセンサと移送フェンスの位置関係を示す図で、（１）は移送途中又は移送完了後の逆送途中を表し、（２）は移送完了時の移送フェンスの位置を示す。
【図６】移送途中に電源オフされ、再度オンされた場合の本発明に係る給紙装置の動作を示すフローチャートである。
【図７】本発明の別の構成における移送動作時での右トレイ側のスイッチ類の配置を説明する図である。
【図８】図７の構成における場合の動作を示すフローチャートである。
【符号の説明】
８移送モータ
９移送フェンス
１０押し付けセンサ
１１ホームセンサ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper feeding device provided in an image forming apparatus such as a laser printer, a facsimile machine, and a copying machine, and more particularly to a so-called tandem type paper feeding device in which two sheet storage portions are arranged in parallel.
[0002]
[Prior art]
For example, as a paper feeding unit for automatically feeding a recording sheet to an image forming unit of an image forming apparatus, a paper feeding device that can accommodate several tens to several thousand recording sheets is conventionally known. . In general, such a sheet feeding apparatus can handle sheet sheets of various sizes, and it is inevitable that sheet sheets other than the maximum size that can be accommodated are stacked and stored. Thus, a dead space is formed. Therefore, for a sheet that is less than half of the maximum size that can be stored, two sheet storage units are arranged in parallel, and the sheets are stored in the first sheet storage unit for feeding to the image forming unit. When there is no longer any sheet, the sheet stored in the second sheet storage unit (auxiliary storage unit) is automatically transferred to the first sheet storage unit so that continuous feeding is possible. A tandem type paper feeding device capable of stacking twice as many sheets has been proposed. In particular, for example, in Japanese Patent Application Laid-Open No. 5-221536, the recording sheet can be supplied to the auxiliary storage unit while feeding the recording sheet of the main storage unit out of the two sheet storage units, thereby improving the copy productivity. A large-volume paper feeder has been proposed.
[0003]
When transferring sheets in such a tandem type sheet feeding device, the back fence for positioning the rear end of the sheet in the first sheet storage unit is tilted forward as the sheet bundle in the second sheet storage unit is transferred. There are also configurations (for example, configurations disclosed in Japanese Patent Application Laid-Open Nos. Hei 3-223031 and Hei 4-28634), but in such cases, the sheet is immediately placed in the second sheet storage portion which is empty due to the structure. Since replenishment cannot be performed, many apparatuses employ a configuration in which the transfer member is returned to the home position after the transfer operation is completed.
[0004]
In such a configuration, when the sheet is transferred, the bottom plate of the first sheet storage unit is lowered, the sheet is transferred by the transfer member, the sheet is fed back to the home position after the transfer is completed, the bottom plate of the first sheet storage unit is raised, and the sheet is fed. The order of start is passed, and this series of operation time is a waiting time for the user.
[0005]
In general, the length of the bottom plate of the first sheet storage unit in the sheet transfer direction is adjusted to the maximum size of sheets that can be loaded so as to be compatible with several types of paper sizes. When the sheet is transferred, the transfer member may reach the operating area of the bottom plate of the first sheet storage unit. If such a situation is assumed, the bottom plate cannot be raised immediately after the sheet transfer is completed. Therefore, normally, the bottom plate starts to rise after the transfer member returns to the home position. However, if the transfer member retracts from the operating area of the bottom plate, it is possible to raise the bottom plate even if it does not return to the home position. In other words, it is possible to shorten the waiting time.
[0006]
[Problems to be solved by the invention]
Therefore, in order to shorten the waiting time as described above, the present inventor uses the state as a trigger for raising the bottom plate when the sheet transfer is completed and the transfer member is retracted in the home position direction to be in a predetermined state. I proposed that earlier. As one aspect, a configuration is disclosed in which a sensor for detecting that the transfer member has withdrawn from the operating region of the bottom plate is additionally installed, and the bottom plate ascending is started using the detection timing of the sensor as a trigger.
[0007]
However, in such a configuration, it is impossible to distinguish between the completion of transfer and the transfer while the transfer member is not detected by the evacuation detection sensor, the transfer completion sensor, or the home position sensor. Therefore, when the power supply of the machine body is turned off and on for some reason during the transfer, the transfer motor is usually driven to continue the transfer operation as a recovery operation. In some cases, the stage where the transfer completion position is completely reached may be after the sensor detection. In such a case, the motor stop signal is not reached indefinitely. Problems such as the occurrence of mancalls will occur.
[0008]
Therefore, in view of the above problems, the present invention can reliably recover after turning on the power regardless of the stop position of the transfer member even if the power of the machine body is turned off while the transfer member is being driven. It is an object of the present invention to provide a paper feeding device that is not unnecessarily long.
[0009]
[Means for Solving the Problems]
The problem is that a first sheet storage unit for stacking a plurality of sheets, elevating means for raising the sheets in the first sheet storage unit to a paper feeding position, and a first arrangement arranged in parallel to the first sheet storage unit. Two sheet storage units, a transfer member that collectively transfers the sheets of the second sheet storage unit to the first sheet storage unit, a first detection unit that detects that the transfer member is at the home position, and the transfer In a paper feeding device including second detection means for detecting that a member is in a transfer completion position and drive means for driving the transfer member, the paper on the second paper storage unit side is transferred to the first paper storage unit. When the power source is turned off at this time, the first detection unit detects the transfer member until a time required for the transfer member in the transfer completion position to reliably move to the upstream side of the second detection unit elapses. Until the above drive means is reversed, the transfer section Was backhaul is solved by controlling to resume the transfer operation thereafter.
[0010]
In addition, a first sheet storage unit for stacking a plurality of sheets, elevating means for raising the sheets in the first sheet storage unit to a paper feeding position, and a second sheet arranged in parallel to the first sheet storage unit A storage unit, a transfer member that collectively transfers the sheets of the second paper storage unit to the first paper storage unit, a first detection unit that detects that the transfer member is at a home position, and the transfer member A second detection unit configured to detect that the transfer completion position is present; and a driving unit configured to drive the transfer member. The transfer member located at the transfer completion position prevents the sheet loaded in the first sheet storage unit from rising. In the paper feeding device having a positional relationship, the second detection means for detecting that the transfer member has retreated toward the home position after the transfer of the paper on the second paper storage unit side to the first paper storage unit is completed. It is also used as a detection means. The avoidance detection is configured to be used as a trigger for raising the sheet to the sheet feeding position, and is in the transfer completion position when the power is turned off when the sheet on the second sheet storage unit side is transferred to the first sheet storage unit. Until the time required for the transfer member to reliably move to the upstream side of the second detection means elapses or until the first detection means detects the transfer member, the drive means is reversed to reversely transfer the transfer member. Then, control is performed so as to restart the transfer operation after that, or a means for detecting the presence or absence of paper in the first paper storage unit is provided, and during the operation of transferring the paper in the second paper storage unit to the first paper storage unit The above problem can also be solved by arranging the sheet presence / absence detection means at a position where the presence of the sheet can be detected only after the second detection means detects the completion of the transfer .
[0011]
Each of the first sheet storage unit and the second sheet storage unit includes a unit for detecting the presence or absence of a sheet, and the interval in the sheet transfer direction of both the sheet presence / absence detection units is the longest feed length of the maximum sheet size that can be stacked. If it is taken large, it is more effective.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The details of the present invention will be described based on examples shown in the drawings.
FIG. 1 is a cross-sectional view of an image forming apparatus using a paper feeding device according to the present invention, and FIG. 2 is a schematic perspective view of a lifting mechanism of a first paper storage unit (hereinafter referred to as “right tray”) 1. FIG. 3 is a schematic perspective view showing a transfer mechanism from the second sheet storage unit (hereinafter referred to as “left tray”) 2.
[0013]
As shown in FIG. 2, the bottom plate 6 of the right tray is suspended by a wire, and the bottom plate 6 is moved up and down by winding or unwinding the wire by driving the lifting motor 5. The sheets P stacked on the right tray 1 are fed one by one to the image forming unit 4 by the sheet feeding means 3 as shown in FIG. When the paper P stacked on the right tray 1 runs out, the elevating motor 5 reverses and descends until the bottom plate 6 is detected by the lower limit sensor 7. When the lower limit sensor 7 detects the bottom plate 6, as shown in FIG. 3, the transfer motor 8 on the left tray 2 side normally rotates, the transfer fence 9 moves to the right tray side, and the sheets stacked on the left tray Transfer P onto the bottom plate of the right tray. When the pressing sensor 10 detects the completion of the transfer, the forward rotation of the transfer motor 8 ends.
[0014]
As shown in FIG. 5, the piece 12 attached to the transfer fence 9 for shielding the pressing sensor 10 includes a slit portion 13 and a shielding portion 14, and the shielding portion 14 located in front of the slit portion 13. Is made longer than the length corresponding to the time when the transfer of the transfer fence and the rise of the bottom plate overlap. The detection of the transfer completion of the pressing sensor 10 is made when the pressing sensor 10 recognizes the slit portion 13 after being shielded by the shielding portion 14, and the bottom plate is raised when the rear end of the shielding portion 14 (the front end when the sheet is transferred) when the transfer fence is reversely fed. ) The rising starts with the passage being pressed and detected by the sensor 10. This series of operations is called a tandem transfer operation. The tandem transfer operation is shown in the flowchart of FIG.
[0015]
However, with the above configuration alone, when the machine body is turned off and the transfer fence 9 is at the position shown in FIG. 5 (1) or the position shown in (2) at that time , It is not possible to identify whether the transfer fence is located in the area.
[0016]
In the present invention, at the time of power on / off of the machine body during transfer, for a certain time, for example, the time when the transfer fence moves by the length of the shielding portion 14 + α, or until the home sensor 11 detects the transfer fence 9, Control is performed to reversely move the transfer fence 9 by reversing the transfer motor 8. Is positioned upstream of the sensor 10 reliably pressed against the transfer fence 9 by way (the position shown in FIG. 5 (1)), it is rotated forward the feed motor 8 and thereafter continues the tandem transport operation. This control operation is shown in a flowchart in FIG.
[0017]
If there is no restriction on the layout, the paper presence detecting means 16 (FIG. 2) of the right tray 1 is moved to a position where the leading edge of the paper is detected after the shielding portion 14 passes the pressing sensor 10 (see FIG. 2). 7 in the area C). With such an arrangement, when the power is turned off / on during transfer, it is guaranteed that the position of the transfer fence 9 is determined based on the paper presence detection means 16 of the right tray 1 to perform accurate recovery. FIG. 8 is a flowchart showing the control operation in this case.
[0018]
Each paper presence detection means 15, 16 is set so that the interval between the paper presence detection means 15 (FIG. 3) in the left tray 2 and the paper presence detection means 16 in the right tray 1 is longer than the maximum paper size that can be stacked. It is preferable that both the paper presence detecting means 15 and 16 are not turned on at the same time in the normal tandem transfer operation. By providing such an arrangement relationship, when the transfer fence 9 is located at the position shown in FIG. 5 ( 2 ) during transfer, the power of the machine body is turned off, and the tray is pulled out from the machine body to transfer the transfer fence. 9 (in FIG. 1), the transfer fence 9 is not at the home position (that is, the home sensor 11 is off) and the paper presence detecting means 15 and 16 are at the same time. Since it is turned on, it is possible to prompt the user to reset the sheet by displaying a message indicating a paper stacking failure on the operation unit.
[0019]
【The invention's effect】
According to the first or second aspect of the invention, when the power is turned off when the paper on the second paper storage unit side is transferred to the first paper storage unit , the transfer member at the transfer completion position is surely connected to the first member. 2 Until the time required to move upstream from the detection means elapses or until the home sensor detects the transfer member, the transfer drive means is reversed to reversely transfer the transfer member, and then the transfer operation is resumed. Therefore, it is possible to avoid a situation in which a service man call is generated or the transfer driving means is damaged.
[0020]
According to the third aspect of the present invention, means for detecting the presence or absence of paper in the first paper storage unit is provided, and the second detection means is configured to move the paper in the second paper storage unit to the first paper storage unit. Since the paper presence / absence detecting means is disposed at a position where the presence of paper can be detected for the first time after the completion of the transfer is detected, the position of the transfer member can be accurately grasped, and a situation such as generation of a service man call or generation of a drive means for transfer occurs. It can be avoided.
[0021]
According to the fourth aspect of the present invention, since the interval in the sheet feeding direction of the two sheet presence / absence detecting means is larger than the longest feeding length of the maximum sheet size that can be stacked, the machine main unit is turned off during the transfer operation. Even if the paper feed tray is pulled out from the machine body and the paper is erroneously stacked on the left side of the transfer member, the transfer member is not at the home position, and the presence of paper is simultaneously turned on by both detection means, Based on this condition, it is possible to prompt the user to reset the sheet by displaying a message indicating a paper stacking failure on the operation unit, and it is possible to avoid a situation such as the occurrence of a service man call or the generation of transfer driving means.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of an image forming apparatus including a paper feeding device according to the present invention.
2 is a perspective view of a raising mechanism of a right tray that is a first sheet storage unit of the sheet feeding device illustrated in FIG. 1. FIG.
3 is a schematic perspective view of a left tray transfer mechanism that is a second sheet storage portion of the sheet feeder shown in FIG. 1. FIG.
4 is a flowchart showing a basic operation in a transfer operation in the paper feeding device shown in FIG. 1. FIG.
FIG. 5 is a diagram showing the positional relationship between the pressing sensor, the home sensor, and the transfer fence during the transfer operation, where (1) represents the transfer in progress or during the reverse transfer after the transfer is completed, and (2) shows the transfer when the transfer is completed. Indicates the position of the fence.
FIG. 6 is a flowchart showing the operation of the sheet feeding device according to the present invention when the power is turned off and then turned on again during transfer.
FIG. 7 is a diagram illustrating the arrangement of switches on the right tray side during a transfer operation according to another configuration of the present invention.
8 is a flowchart showing the operation in the case of the configuration of FIG.
[Explanation of symbols]
8 Transfer motor 9 Transfer fence 10 Press sensor 11 Home sensor

Claims

複数枚の用紙を積載する第１用紙収容部と、当該第１用紙収容部の用紙を給紙位置まで上昇させる昇降手段と、上記第１用紙収容部に対し並列配置された第２用紙収容部と、当該第２用紙収容部の用紙を第１用紙収容部へ一括して移送する移送部材と、当該移送部材がホーム位置にあることを検知する第１検知手段と、上記移送部材が移送完了位置にあることを検知する第２検知手段と、上記移送部材を駆動する駆動手段とを備える給紙装置において、
第２用紙収容部側の用紙を第１用紙収容部へ移送する際に電源がオフオンされた場合、移送完了位置にある移送部材が確実に第２検知手段よりも上流側に移動するのに要する時間が経過するまで又は上記第１検知手段が移送部材を検知するまで、上記駆動手段を逆転して移送部材を逆送させ、しかる後に移送動作を再開するように制御することを特徴とする給紙装置。A first paper storage unit for stacking a plurality of papers; elevating means for raising the paper in the first paper storage unit to a paper feed position; and a second paper storage unit arranged in parallel to the first paper storage unit A transfer member that collectively transfers the sheets of the second sheet storage unit to the first sheet storage unit, a first detection unit that detects that the transfer member is at the home position, and the transfer member is completely transferred In a paper feeding device comprising a second detection means for detecting the position and a drive means for driving the transfer member,
When the power is turned off when the sheet on the second sheet storage unit is transferred to the first sheet storage unit, it is necessary for the transfer member at the transfer completion position to reliably move upstream from the second detection unit. The feed means is controlled to reversely reverse the drive means until time elapses or until the first detection means detects the transfer member, and then the transfer operation is resumed. Paper device.

複数枚の用紙を積載する第１用紙収容部と、当該第１用紙収容部の用紙を給紙位置まで上昇させる昇降手段と、上記第１用紙収容部に対し並列配置された第２用紙収容部と、当該第２用紙収容部の用紙を第１用紙収容部へ一括して移送する移送部材と、当該移送部材がホーム位置にあることを検知する第１検知手段と、上記移送部材が移送完了位置にあることを検知する第２検知手段と、上記移送部材を駆動する駆動手段とを備え、移送完了位置にある移送部材が第１用紙収容部に積載されている用紙の上昇を妨げる位置関係を有する給紙装置において、
第２用紙収容部側の用紙を第１用紙収容部へ移送終了後に移送部材がホーム位置方向へ退避したことを検知するための第３検知手段を上記第２検知手段で兼用し、当該検知手段での退避検知を給紙位置への用紙上昇トリガーに用いるように構成し、第２用紙収容部側の用紙を第１用紙収容部へ移送する際に電源がオフオンされた場合に、移送完了位置にある移送部材が確実に第２検知手段よりも上流側に移動するのに要する時間が経過するまで又は上記第１検知手段が移送部材を検知するまで、上記駆動手段を逆転して移送部材を逆送させ、しかる後に移送動作を再開するように制御することを特徴とする給紙装置。A first paper storage unit for stacking a plurality of papers; elevating means for raising the paper in the first paper storage unit to a paper feed position; and a second paper storage unit arranged in parallel to the first paper storage unit A transfer member that collectively transfers the sheets of the second sheet storage unit to the first sheet storage unit, a first detection unit that detects that the transfer member is at the home position, and the transfer member is completely transferred A positional relationship that includes second detecting means for detecting the position and driving means for driving the transfer member, and the transfer member at the transfer completion position prevents the paper loaded in the first paper storage portion from rising. In a paper feeder having
The second detection means also serves as third detection means for detecting that the transfer member is retracted in the home position direction after the transfer of the sheet on the second paper storage section side to the first paper storage section. When the power supply is turned off when the sheet on the second sheet storage unit side is transferred to the first sheet storage unit, the transfer completion position is detected. Until the time required for the transfer member to reliably move upstream from the second detection means elapses or until the first detection means detects the transfer member, the drive means is reversed to move the transfer member. A paper feeding device that performs reverse feeding and then controls to resume the transfer operation.

複数枚の用紙を積載する第１用紙収容部と、当該第１用紙収容部の用紙を給紙位置まで上昇させる昇降手段と、上記第１用紙収容部に対し並列配置された第２用紙収容部と、当該第２用紙収容部の用紙を第１用紙収容部へ一括して移送する移送部材と、当該移送部材がホーム位置にあることを検知する第１検知手段と、上記移送部材が移送完了位置にあることを検知する第２検知手段と、上記移送部材を駆動する駆動手段とを備え、移送完了位置にある移送部材が第１用紙収容部に積載されている用紙の上昇を妨げる位置関係を有する給紙装置において、
第１用紙収容部の用紙の有無を検知する手段を設け、第２用紙収容部の用紙を第１用紙収容部へ移送する動作時に、上記第２検知手段が移送完了を検知した後に始めて用紙有りを検知できる位置に、上記用紙有無検知手段を配置したことを特徴とする給紙手段。A first paper storage unit for stacking a plurality of papers; elevating means for raising the paper in the first paper storage unit to a paper feed position; and a second paper storage unit arranged in parallel to the first paper storage unit A transfer member that collectively transfers the sheets of the second sheet storage unit to the first sheet storage unit, a first detection unit that detects that the transfer member is at the home position, and the transfer member is completely transferred A positional relationship that includes second detecting means for detecting the position and driving means for driving the transfer member, and the transfer member at the transfer completion position prevents the paper loaded in the first paper storage portion from rising. In a paper feeder having
A means for detecting the presence or absence of paper in the first paper storage unit is provided, and there is paper only after the second detection means detects completion of transfer during the operation of transferring the paper in the second paper storage unit to the first paper storage unit. The paper feeding means is characterized in that the paper presence / absence detecting means is arranged at a position where it can be detected .

第１用紙収容部と第２用紙収容部のそれぞれに用紙の有無を検知する手段を備え、両方の用紙有無検知手段の用紙移送方向の間隔が積載可能な最大用紙サイズの最長送り長さよりも大きくとられていることを特徴とする請求項１〜３のいずれか一項に記載の給紙手段。 Each of the first paper storage unit and the second paper storage unit is provided with means for detecting the presence or absence of paper, and the interval in the paper transfer direction of both paper presence / absence detection means is larger than the longest feed length of the maximum paper size that can be stacked. The sheet feeding means according to any one of claims 1 to 3, wherein the sheet feeding means is employed.