JP2020121832A

JP2020121832A - Paper cassette and image forming apparatus

Info

Publication number: JP2020121832A
Application number: JP2019013839A
Authority: JP
Inventors: ダンロンブイ; Dang Long V
Original assignee: Kyocera Document Solutions Inc
Current assignee: Kyocera Document Solutions Inc
Priority date: 2019-01-30
Filing date: 2019-01-30
Publication date: 2020-08-13

Abstract

To provide a paper cassette capable of buffering an impact applied to a pickup roller from a lift plate by a simple structure.SOLUTION: A paper cassette comprises a lift plate 23 that is supported rotatably between a lowered position and an elevated position, a first biasing member 25 that biases the lift plate 23 from the lowered position to the elevated position, and a buffer member 31 that is supported in a reference position interfering with a rotary locus of a front edge of the lift plate 23 and buffers the rotation speed of the lift plate 23 biased by the first biasing member 25. The buffer member 31 abuts against the lift plate 23 biased by the first biasing member 25 and rotates upward from the reference position while giving a predetermined load to the lift plate 23, rotates downward after a passage of the lift plate 23 and is supported in the reference position, abuts against the lift plate 23 and rotates downward when the lift plate 23 rotates from the elevated position to the lowered position, and rotates upward and is supported at the reference position after a passage of the lift plate 23.SELECTED DRAWING: Figure 5

Description

本発明は、画像が形成される用紙を収容する給紙カセット及び画像形成装置に関する。 The present invention relates to a paper feed cassette that stores paper on which an image is formed and an image forming apparatus.

複合機やプリンター等の画像形成装置は、着脱可能な給紙カセットを備えている。給紙カセットには、用紙が載置されるリフト板が備えられている。リフト板は昇降可能であり、用紙を収容する際には下降させて用紙を積載し、給紙カセットが装着されると上昇して、最上位の用紙をピックアップローラーに当接させるようになっている。 An image forming apparatus such as a multifunction peripheral or a printer includes a detachable paper feed cassette. The paper feed cassette is provided with a lift plate on which the paper is placed. The lift plate can be moved up and down.When the paper is stored, it is lowered to load the paper, and when the paper cassette is installed, it is lifted to bring the topmost paper into contact with the pickup roller. There is.

給紙カセットによっては、リフト板がバネで付勢されて上昇して、最上位の用紙がピックアップローラーに当接するように構成される場合がある。リフト板に載置された用紙の枚数が多い場合は、用紙によってバネの付勢力が緩衝されるので、リフト板からピックアップローラーに強い衝撃はかからないが、リフト板に載置される用紙の枚数が少ない場合には、リフト板からピックアップローラーに強い衝撃がかかることがある。すると、騒音が発生したりピックアップローラーの位置が変化したりする問題が生じる。 Depending on the paper feed cassette, the lift plate may be biased by a spring to move up and the uppermost paper may come into contact with the pickup roller. When the number of sheets of paper placed on the lift plate is large, the biasing force of the spring is buffered by the paper, so a strong impact is not applied to the pickup roller from the lift plate, but the number of sheets of paper placed on the lift plate is reduced. If the amount is small, a strong impact may be applied from the lift plate to the pickup roller. Then, there arises a problem that noise is generated or the position of the pickup roller is changed.

特許文献１に記載の給紙カセットは、給紙カセットが筐体に装着された状態で、リフト板が上方へ変位する変位速度を段階的に減速するリフト駆動ユニットを備えている。 The paper feed cassette described in Patent Document 1 includes a lift drive unit that gradually reduces the displacement speed at which the lift plate is displaced upward when the paper feed cassette is mounted in the housing.

特開２０１７−１１４６６９号公報JP, 2017-114669, A

しかしながら上記特許文献１に記載されている給紙カセットでは、リフト駆動ユニットが、アクチュエータや二段カムを備えた複雑な構成を有している。 However, in the paper feeding cassette described in Patent Document 1, the lift drive unit has a complicated structure including an actuator and a two-stage cam.

そこで本発明は上記事情を考慮し、簡易な構成でリフト板からピックアップローラーにかかる衝撃を緩衝できる給紙カセットとこの給紙カセットを備えた画像形成装置を提供することを目的とする。 In view of the above circumstances, the present invention has an object to provide a paper feed cassette capable of buffering the impact applied to the pickup roller from the lift plate with a simple configuration, and an image forming apparatus including the paper feed cassette.

上記目的を達成するため、本発明の給紙カセットは、ピックアップローラーを備えるカセット収容部に装着され、前記ピックアップローラーによって所定の給送方向に給送される用紙を収納する給紙カセットであって、前記用紙を収容する本体部と、前記本体部内に、前記用紙が載置される下降位置と、載置された前記用紙を前記ピックアップローラーに接触させる上昇位置と、の間を、前記給送方向の上流側の端部を支点として回動可能に支持されるリフト板と、前記カセット収容部に装着されることで、前記リフト板を前記下降位置から前記上昇位置に付勢する第１の付勢部材と、前記下降位置と前記上昇位置との間で回動する前記リフト板の先端縁の回動軌跡と干渉する基準位置に支持され、前記第１の付勢部材で付勢される前記リフト板の回動速度を減速する緩衝部材と、を備え、前記緩衝部材は、前記下降位置から前記上昇位置へ前記第１の付勢部材で付勢されて回動する前記リフト板に当接して、該リフト板に所定の負荷を与えつつ前記基準位置から上方に回動し、前記リフト板が通過した後で下方に回動して前記基準位置に保持され、前記リフト板が前記上昇位置から前記下降位置に回動する際に、前記リフト板に当接して下方に回動し、前記リフト板が通過した後で上方に回動して前記基準位置に保持されることを特徴とする。 In order to achieve the above-mentioned object, a sheet feeding cassette of the present invention is a sheet feeding cassette which is mounted in a cassette housing portion having a pickup roller and stores sheets fed in a predetermined feeding direction by the pickup roller. The feeding unit is provided between a main body for accommodating the paper, a lowered position for loading the paper in the main body, and an elevated position for bringing the placed paper into contact with the pickup roller. A lift plate that is rotatably supported with an upstream end in the direction of rotation as a fulcrum, and a first plate that is attached to the cassette housing portion to urge the lift plate from the lowered position to the raised position. The urging member is supported at a reference position that interferes with the rotation locus of the leading edge of the lift plate that rotates between the lowered position and the raised position, and is urged by the first urging member. A cushioning member that reduces the rotation speed of the lift plate, the cushioning member contacting the lift plate that is biased by the first biasing member from the lowered position to the raised position to rotate. When contacting with each other, the lift plate is rotated upward from the reference position while applying a predetermined load to the lift plate, and after passing through the lift plate, the lift plate is rotated downward and held at the reference position, and the lift plate is raised. When rotating from the position to the lowered position, the lift plate comes into contact with the lift plate and rotates downward, and after the lift plate passes, it rotates upward and is held at the reference position. To do.

本発明の給紙カセットにおいて、前記本体部は、前記給送方向の下流側の端部に、前板で区画されて、前記緩衝部材が収容される前壁部を有し、前記前板には、上下方向に沿って形成された切り欠きが形成され、前記リフト板は、前記先端縁から突出する突出片を有し、前記リフト板の回動時、前記突出片が前記切り欠きを通過する際に、前記緩衝部材に当接することを特徴としてもよい。 In the paper feed cassette of the present invention, the main body portion has a front wall portion, which is partitioned by a front plate and accommodates the buffer member, at the end portion on the downstream side in the feeding direction, and the front plate is provided. Has a notch formed along the vertical direction, the lift plate has a protruding piece protruding from the tip edge, and the protruding piece passes through the notch when the lift plate rotates. When doing so, it may be characterized in that it comes into contact with the cushioning member.

本発明の給紙カセットにおいて、前記緩衝部材は、前記本体部に上下方向に回動可能に支持されて、前記リフト板の回動時に該リフト板が当接する回動部材と、前記回動部材に対して相対回転する支持部材と、前記支持部材を前記本体部に対して前記基準位置に付勢すると共に、前記回動部材を前記支持部材に対して前記基準位置に付勢する第２の付勢部材と、を備えていることを特徴としてもよい。 In the paper feed cassette of the present invention, the cushioning member is rotatably supported by the main body in a vertical direction, and the rotating member comes into contact with the lift plate when the lift plate rotates, and the rotating member. A second supporting member that rotates relative to the support member, and a second member that urges the supporting member to the reference position with respect to the main body portion and urges the rotating member to the reference position with respect to the supporting member. A biasing member may be provided.

本発明の給紙カセットにおいて、前記回動部材は、前記本体部に上下方向に回転可能に支持される軸部と、前記リフト板の昇降時に該リフト板が当接する当接部と、を有し、前記支持部材は、前記軸部に外嵌して該軸部に対して回転する円筒部と、前記本体部に係止される係止部と、を有し、前記第２の付勢部材は、前記支持部材を前記本体部に対して位置決めする第１ねじりコイルバネと、前記回動部材を前記支持部材に対して位置決めする第２ねじりコイルバネと、を有し、前記リフト板が上方に回動して下方から前記当接部に当接すると、前記支持部材は前記係止部が前記本体部に係止されることで前記基準位置からの回転が規制される一方で、前記回動部材は前記第２ねじりコイルバネの付勢力に抗して前記支持部材に対して上方に回動し、その後、前記当接部が前記リフト板から離間すると、前記回動部材が前記第２ねじりコイルバネで付勢されて前記基準位置に回動し、前記リフト板が下方に回動して上方から前記当接部に当接すると、前記回動部材が下方に回動すると共に、前記支持部材は前記第１ねじりコイルバネの付勢力に抗して前記基準位置から回転し、その後、前記当接部が前記リフト板から離間すると、前記支持部材が前記第１ねじりコイルバネで付勢されて、前記基準位置に回転することを特徴としてもよい。 In the paper feed cassette of the present invention, the rotating member has a shaft portion rotatably supported by the main body portion in a vertical direction, and an abutting portion with which the lift plate abuts when the lift plate is raised and lowered. The support member has a cylindrical portion that is fitted onto the shaft portion and rotates with respect to the shaft portion, and a locking portion that is locked by the main body portion. The member has a first torsion coil spring that positions the support member with respect to the main body portion, and a second torsion coil spring that positions the rotating member with respect to the support member, and the lift plate moves upward. When the support member is rotated and comes into contact with the contact portion from below, the support member is prevented from rotating from the reference position by the engagement portion being retained by the main body portion, while the support member is rotated. The member rotates upward with respect to the support member against the biasing force of the second torsion coil spring, and when the contact portion is separated from the lift plate thereafter, the rotation member causes the second torsion coil spring to move. When the lift plate is urged to rotate to the reference position and the lift plate rotates downward to come into contact with the contact portion from above, the rotation member rotates downward and the support member moves. When the contact portion is separated from the lift plate by rotating from the reference position against the urging force of the first torsion coil spring, the support member is urged by the first torsion coil spring, and the reference member is urged. It may be characterized by rotating to a position.

本発明の画像形成装置は、前記給紙カセットと、前記カセット収容部に装着された前記給紙カセットから前記ピックアップローラーによって給送された用紙に画像を形成する画像形成部と、を備えていることを特徴とする。 An image forming apparatus of the present invention includes the paper feed cassette, and an image forming unit that forms an image on a paper sheet fed by the pickup roller from the paper feed cassette mounted in the cassette housing unit. It is characterized by

本発明によれば、付勢部材で付勢されたリフト板は、一旦緩衝部材に当接した後で、最上位の用紙がピックアップローラーに当接するまで上昇する。このように、付勢部材の付勢力が緩衝されるので、リフト板に載置された用紙の枚数が少ない場合にも、ピックアップローラーがリフト板から受ける衝撃を緩和できる。 According to the present invention, the lift plate urged by the urging member once abuts on the cushioning member and then rises until the uppermost sheet abuts on the pickup roller. In this way, the urging force of the urging member is buffered, so that even when the number of sheets of paper placed on the lift plate is small, the impact that the pickup roller receives from the lift plate can be mitigated.

本発明の一実施形態に係るプリンターを示す斜視図である。It is a perspective view showing a printer concerning one embodiment of the present invention. 本発明の一実施形態に係る給紙カセットを示す斜視図である。FIG. 3 is a perspective view showing the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットのリフト板の先端部を示す斜視図である。FIG. 3 is a perspective view showing a front end portion of a lift plate of the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が下降した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where the lift plate is lowered in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が上昇して緩衝部材に当接した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where the lift plate is raised and abuts on the cushioning member in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が上昇して緩衝部材が上方に回動した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where the lift plate is lifted and the cushioning member is rotated upward in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が上昇してピックアップローラーに当接した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where a lift plate is raised and abuts on a pickup roller in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が下降して緩衝部材に当接した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where the lift plate descends and comes into contact with the cushioning member in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が下降して緩衝部材が下方に回動した状態を示す断面図である。FIG. 6 is a cross-sectional view showing a state where the lift plate is lowered and the cushioning member is rotated downward in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、緩衝部材を示す斜視図である。FIG. 6 is a perspective view showing a cushioning member in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、緩衝部材を示す斜視図である。FIG. 6 is a perspective view showing a cushioning member in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、緩衝部材を示す断面図である。FIG. 6 is a cross-sectional view showing a cushioning member in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が上昇して上方に回動した緩衝部材を示す断面図である。FIG. 6 is a cross-sectional view showing a cushioning member in which a lift plate is lifted and pivoted upward in the paper feed cassette according to the embodiment of the present invention. 本発明の一実施形態に係る給紙カセットにおいて、リフト板が下降して下方に回動した緩衝部材を示す断面図である。FIG. 6 is a cross-sectional view showing a cushioning member in which a lift plate descends and pivots downward in a paper feed cassette according to an embodiment of the present invention.

以下、図面を参照しつつ、本発明の一実施形態に係る画像形成装置及び給紙カセットについて説明する。 Hereinafter, an image forming apparatus and a sheet feeding cassette according to an exemplary embodiment of the present invention will be described with reference to the drawings.

まず、図１を参照して、画像形成装置の全体の構成について説明する。図１は、本発明の一実施形態に係る画像形成装置の概略を示す模式図である。各図のFｒ、Rｒ、Ｌ、Ｒはそれぞれ画像形成装置の前側、後側、左側、右側を示す。 First, the overall configuration of the image forming apparatus will be described with reference to FIG. FIG. 1 is a schematic diagram showing an outline of an image forming apparatus according to an embodiment of the present invention. In each figure, Fr, Rr, L, and R respectively indicate the front side, rear side, left side, and right side of the image forming apparatus.

画像形成装置１は、中空部を有する略直方体形状の筐体３を備えている。筐体３の下部には、給紙カセット５が着脱可能に装着されるカセット収容部７が形成されている。筐体３の前壁には、カセット収容部７に連通する開口７ａが形成されて、給紙カセット５は開口７ａを通してカセット収容部７に着脱される。筐体３の上面には、排出トレイ９が形成されている。 The image forming apparatus 1 includes a substantially rectangular parallelepiped casing 3 having a hollow portion. At the bottom of the housing 3, a cassette housing 7 is formed in which the paper feed cassette 5 is detachably mounted. An opening 7a communicating with the cassette housing portion 7 is formed on the front wall of the housing 3, and the paper feed cassette 5 is attached to and detached from the cassette housing portion 7 through the opening 7a. A discharge tray 9 is formed on the upper surface of the housing 3.

筐体３内には、給紙装置１１と、画像形成部１３と、が設けられている。給紙装置１１は、カセット収容部７に備えられて、カセット収容部７に装着された給紙カセット５から用紙を給送方向に沿って送り出す。画像形成部１３は、給紙装置１１によって送り出された用紙にトナー像を形成する。さらに、筐体３内には、給紙装置１１から画像形成部１３を通って排出トレイ９に向かって用紙が搬送される搬送経路が形成されている。 A paper feeding device 11 and an image forming unit 13 are provided in the housing 3. The paper feeding device 11 is provided in the cassette housing portion 7 and feeds the paper from the paper feeding cassette 5 mounted in the cassette housing portion 7 along the feeding direction. The image forming unit 13 forms a toner image on the sheet fed by the sheet feeding device 11. Further, in the housing 3, a conveyance path is formed through which the sheet is conveyed from the sheet feeding device 11 through the image forming unit 13 toward the discharge tray 9.

次に、給紙カセット５と給紙装置１１とについて、図２、図３及び図４〜図９を参照して説明する。図２は給紙カセットを示す斜視図、図３は給紙カセットのリフト板の突片を示す斜視図、図４〜図９は給紙カセットを示す断面図である。 Next, the paper feed cassette 5 and the paper feed device 11 will be described with reference to FIGS. 2, 3, and 4 to 9. 2 is a perspective view showing a paper feed cassette, FIG. 3 is a perspective view showing a protrusion of a lift plate of the paper feed cassette, and FIGS. 4 to 9 are sectional views showing the paper feed cassette.

まず、図２を主に参照して、給紙カセット５について説明する。給紙カセット５は、本体部２１と、本体部２１に昇降可能に支持されるリフト板２３と、リフト板２３と本体部２１との間に配置される第１の付勢部材としてのボトムバネ２５（図４〜図９参照）と、本体部２１に給送方向Ｙと直交する幅方向Ｗにスライド可能に支持される一対のサイドカーソル２７と、本体部２１に給送方向Ｙ及びその反対方向にスライド可能に支持されるエンドカーソル２９と、ボトムバネ２５の付勢力を緩衝する緩衝部材３１（図３〜図９参照）と、を備えている。 First, the paper feed cassette 5 will be described mainly with reference to FIG. The sheet feeding cassette 5 includes a main body portion 21, a lift plate 23 that is supported by the main body portion 21 so as to be capable of moving up and down, and a bottom spring 25 that is disposed between the lift plate 23 and the main body portion 21 and serves as a first biasing member. (See FIGS. 4 to 9), a pair of side cursors 27 slidably supported by the main body portion 21 in the width direction W orthogonal to the feeding direction Y, and the main body portion 21 in the feeding direction Y and the opposite direction. An end cursor 29 slidably supported on the bottom of the bottom spring 25 and a cushioning member 31 (see FIGS. 3 to 9) for cushioning the urging force of the bottom spring 25 are provided.

図２に示されるように、本体部２１は、上面が開口した浅いトレイ形状であり、底板２１ａと、前板２１ｂと、左右の側板２１ｃと、を有している。また、本体部２１には、前板２１ｂの外側（前側）にカバー板４３が装着されている。カバー板４３は、給紙カセット５がカセット収容部７に装着されると、筐体３の開口７ａを閉じる。 As shown in FIG. 2, the main body 21 has a shallow tray shape with an open upper surface, and has a bottom plate 21a, a front plate 21b, and left and right side plates 21c. In addition, a cover plate 43 is attached to the main body portion 21 outside (front side) of the front plate 21b. The cover plate 43 closes the opening 7 a of the housing 3 when the paper feed cassette 5 is mounted in the cassette housing portion 7.

本体部２１は、前板２１ｂよりも給送方向Ｙの上流側の用紙収容部２１Ａと、下流側の前壁部２１Ｂと、に区画されている。前壁部２１Ｂは、前板２１ｂとカバー板４３との間に中空状に形成されている。 The main body portion 21 is partitioned into a sheet storage portion 21A on the upstream side in the feeding direction Y with respect to the front plate 21b and a front wall portion 21B on the downstream side. The front wall portion 21B is formed in a hollow shape between the front plate 21b and the cover plate 43.

図３に示されるように、前板２１ｂは、底板２１ａから略垂直に立設する先端壁２１ｄと、先端壁２１ｄから給送方向Ｙに沿って湾曲するガイド壁２１ｅと、を有している。ガイド壁２１ｅには、幅方向Ｗの中央部に、分離ローラー４５（図２参照）が回転可能に支持されている。また、分離ローラー４５の両側において、先端壁２１ｄとガイド壁２１ｅとの角部か、先端壁２１ｄの下端まで、上下方向に沿って切り欠き４７が形成されている。さらに、前壁部２１Ｂには、切り欠き４７の両側に、幅方向Ｗに対向する一対の板状のリブ４９が形成されている。図４等に示されるように、両リブ４９には、幅方向Ｗに沿った同軸上に軸孔５１が形成されている。また、一対のリブ４９の一方には、軸孔５１の近傍（上方）に、板片状の凸片５３が形成されている。 As shown in FIG. 3, the front plate 21b has a front end wall 21d that stands substantially vertically from the bottom plate 21a, and a guide wall 21e that curves from the front end wall 21d along the feeding direction Y. .. A separation roller 45 (see FIG. 2) is rotatably supported at the center of the guide wall 21e in the width direction W. Further, on both sides of the separation roller 45, a notch 47 is formed along the vertical direction up to the corner of the tip wall 21d and the guide wall 21e or the lower end of the tip wall 21d. Further, on the front wall portion 21B, a pair of plate-shaped ribs 49 facing each other in the width direction W are formed on both sides of the notch 47. As shown in FIG. 4 and the like, both ribs 49 are formed with shaft holes 51 coaxially along the width direction W. Further, a plate-like convex piece 53 is formed on one of the pair of ribs 49 in the vicinity of (above) the shaft hole 51.

再度図２を参照して、用紙収容部２１Ａに対応する底板２１ａは、最大サイズの用紙を載置可能な寸法を有している。用紙収容部２１Ａにおいて、底板２１ａの下流側の端部には、ロック板４１が、幅方向Ｗにスライド可能に支持されている。ロック板４１は、底板２１ａの幅の半分程度の長さの細長い板片であり、一端にはテーパー状の被押圧部４１ａが形成され、他端には係合部４１ｂ（図４等参照）が形成されている。ロック板４１は、被押圧部４１ａが、本体部２１の右側板２１ｃに形成された開口から外側に突出するように、付勢部材（図示省略）によって付勢されている。給紙カセット５がカセット収容部７に装着されると、カセット収容部７に設けられた押圧部によって被押圧部４１ａが押圧されて、付勢部材の付勢力に抗してロック板４１が内方向（底板２１ａの幅方向Wの中心に向かう方向）にスライドするようになっている。 Referring again to FIG. 2, the bottom plate 21a corresponding to the sheet storage portion 21A has a size capable of holding the maximum size sheet. A lock plate 41 is slidably supported in the width direction W at the downstream end of the bottom plate 21a in the sheet storage unit 21A. The lock plate 41 is an elongated plate piece having a length about half the width of the bottom plate 21a, and a tapered pressed portion 41a is formed at one end and an engaging portion 41b at the other end (see FIG. 4 and the like). Are formed. The lock plate 41 is biased by a biasing member (not shown) such that the pressed portion 41a projects outward from an opening formed in the right side plate 21c of the main body portion 21. When the paper feed cassette 5 is mounted in the cassette housing portion 7, the pressed portion 41a is pressed by the pressing portion provided in the cassette housing portion 7, and the lock plate 41 is moved inward against the biasing force of the biasing member. It slides in the direction (direction toward the center in the width direction W of the bottom plate 21a).

用紙収容部２１Ａにおいて、左右の側板２１ｃの前端側には、それぞれ上下方向に沿ったスリット５５が形成されている。さらに、左右の側板２１ｃの内側の面には、給送方向Ｙにおける略中央部に、幅方向Ｗに沿った同軸上にそれぞれピン５７が立設されている。 In the sheet storage portion 21A, slits 55 are formed along the vertical direction on the front end sides of the left and right side plates 21c. Further, on the inner surfaces of the left and right side plates 21c, pins 57 are erected coaxially along the width direction W at substantially the center in the feeding direction Y, respectively.

リフト板２３について、図２を主に参照して説明する。リフト板２３は、本体部２１の用紙収容部２１Ａと同等の幅と、用紙収容部２１Ａの長さよりも短い長さとを有し、用紙が積載可能な平板である。リフト板２３は、用紙収容部２１Ａの下流側の部分に配置されている。リフト板２３の左右端部には、サイドカーソル２７が通過するための矩形状の切り欠き２３ａが形成され、後端部には、エンドカーソル２９が通過するための矩形状の切り欠き２３ｂが形成されている。以降、リフト板２３の、切り欠き２３ａよりも前側（下流側）の部分を前板部とし、切り欠き２３ａよりも後側（上流側）の部分を後板部とする。 The lift plate 23 will be described mainly with reference to FIG. The lift plate 23 is a flat plate having a width equal to that of the sheet storage portion 21A of the main body portion 21 and a length shorter than the length of the sheet storage portion 21A, and on which sheets can be stacked. The lift plate 23 is arranged at a portion on the downstream side of the paper storage unit 21A. A rectangular notch 23a for the side cursor 27 to pass through is formed at the left and right ends of the lift plate 23, and a rectangular notch 23b for the end cursor 29 to pass through is formed at the rear end. Has been done. Hereinafter, a portion of the lift plate 23 on the front side (downstream side) of the notch 23a is referred to as a front plate portion, and a portion of the lift plate 23 on the rear side (upstream side) of the notch 23a is referred to as a rear plate portion.

リフト板２３の前板部の先端縁には、幅方向Ｗに所定の間隔を開けて２つの突片６１が形成されている。図３にも示されるように、２つの突片６１は、前板２１ｂの２つの切り欠き４７に対応している。 Two protrusions 61 are formed at the front edge of the front plate portion of the lift plate 23 with a predetermined space in the width direction W. As shown in FIG. 3, the two protrusions 61 correspond to the two notches 47 in the front plate 21b.

さらに、リフト板２３の前板部の左右側縁には、外方向に突出する左右の突片６３が形成されている。左右の突片６３は、本体部２１の左右の側板２１ｃのスリット５５にそれぞれ挿入されている。さらに、リフト板２３の後板部には、左右側縁に沿って、左右の支持片２３ｃが立設されている。左右の支持片２３ｃは、本体部２１の左右の側板２１ｃのピン５７にそれぞれ軸支されている。リフト板２３は、本体部２１の底板２１ａ上に重ねられる下限位置（下降位置）と、各突片６３が各スリット５５の上縁に係止されるまで前方に向かって上向き傾斜する上限位置との間を、ピン５７を中心として上下方向に回動する（昇降する）。この際、リフト板２３の突片６１は、本体部２１の前板２１ｂの切り欠き４７内を移動する。 Further, left and right projecting pieces 63 projecting outward are formed on the left and right side edges of the front plate portion of the lift plate 23. The left and right protrusions 63 are inserted into the slits 55 of the left and right side plates 21c of the main body 21, respectively. Further, on the rear plate portion of the lift plate 23, left and right support pieces 23c are provided upright along the left and right side edges. The left and right support pieces 23c are pivotally supported by the pins 57 of the left and right side plates 21c of the main body 21, respectively. The lift plate 23 has a lower limit position (lowered position) overlaid on the bottom plate 21a of the main body portion 21 and an upper limit position that is inclined upward toward the front until each protrusion 63 is locked to the upper edge of each slit 55. Between them, the pin 57 is rotated in the vertical direction (moves up and down). At this time, the protrusion 61 of the lift plate 23 moves in the notch 47 of the front plate 21b of the main body 21.

さらに、図４等に示されるように、リフト板２３の前板部の幅方向Ｗの中央部には、下方に突出する係合片６５が形成されている。 Further, as shown in FIG. 4 and the like, an engaging piece 65 projecting downward is formed at the central portion of the front plate portion of the lift plate 23 in the width direction W.

リフト板２３を押し下げると、係合片６５がロック板４１の係合部４１ｂに当接して、係合部４１ｂを下方に押圧する。すると、係合部４１ｂが幅方向Ｗに沿って内方向（左方向）に案内され、付勢部材の付勢力に抗してロック板４１が内方向に移動する。リフト板２３がさらに押し下げられて係合片６５が係合部４１ｂから下方に離間すると、ロック板４１は付勢部材で付勢されて外方向にスライドして、係合部４１ｂが係合片６５に係合する。これにより、リフト板２３とロック板４１とが係合して、リフト板２３は下限位置に上昇不能にロックされる。一方で、給紙カセット５がカセット収容部７に装着されると、ロック板４１の被押圧部４１ａがカセット収容部７の押圧部で押されて、ロック板４１が付勢部材の付勢力に抗して内方向へスライドして、係合部４１ｂが係合片６５から離間する。これにより、リフト板２３とロック板４１との係合が解除され、リフト板２３の下限位置でのロックが解除されて、リフト板２３は上昇可能となる。 When the lift plate 23 is pushed down, the engagement piece 65 comes into contact with the engagement portion 41b of the lock plate 41 and presses the engagement portion 41b downward. Then, the engaging portion 41b is guided inward (leftward) along the width direction W, and the lock plate 41 moves inward against the urging force of the urging member. When the lift plate 23 is further pushed down and the engaging piece 65 is separated downward from the engaging portion 41b, the lock plate 41 is biased by the biasing member and slides outward, so that the engaging portion 41b moves. Engage 65. As a result, the lift plate 23 and the lock plate 41 are engaged with each other, and the lift plate 23 is locked in the lower limit position so that it cannot be lifted. On the other hand, when the paper feed cassette 5 is attached to the cassette housing portion 7, the pressed portion 41a of the lock plate 41 is pushed by the pressing portion of the cassette housing portion 7, and the lock plate 41 is biased by the biasing member. By sliding inward, the engaging portion 41b is separated from the engaging piece 65. As a result, the engagement between the lift plate 23 and the lock plate 41 is released, the lock of the lift plate 23 at the lower limit position is released, and the lift plate 23 can be raised.

ボトムバネ２５はコイルスプリングであり、図４等に示されるように、本体部２１の底板２１ａとリフト板２３の前板部との間に配置されている。ボトムバネ２５は、リフト板２３を底板２１ａに対して上方に付勢する。前述のように、給紙カセット５がカセット収容部７に装着されて、リフト板２３が上昇可能となると、リフト板２３はボトムバネ２５で付勢されて、ピン５７を中心として上限位置へ回動する。 The bottom spring 25 is a coil spring, and is arranged between the bottom plate 21a of the main body 21 and the front plate of the lift plate 23 as shown in FIG. The bottom spring 25 biases the lift plate 23 upward with respect to the bottom plate 21a. As described above, when the paper feed cassette 5 is mounted in the cassette housing portion 7 and the lift plate 23 can be lifted, the lift plate 23 is urged by the bottom spring 25 to rotate about the pin 57 to the upper limit position. To do.

一対のサイドカーソル２７は、図２に示されるように、それぞれ、給送方向Ｙに平行な規制板と、規制板の下端から屈曲するラック板と、を有している。一対のサイドカーソル２７は、規制板が幅方向Ｗに対向して、ラック板が左右方向にスライド可能に底板２１ａに支持される。各ラック板は、底板２１ａに支持されたピニオン（図示省略）と噛み合っている。これにより、一対のサイドカーソル２７が同期で反対方向にスライドする。一対のサイドカーソル２７を互いに接近する方向にスライドさせて、各規制板をリフト板２３の切り欠き２３ａを通ってリフト板２３に載置された用紙の両側縁に当接させることで、用紙が幅方向Ｗに整合される。 As shown in FIG. 2, each of the pair of side cursors 27 has a regulation plate parallel to the feeding direction Y and a rack plate bent from the lower end of the regulation plate. The pair of side cursors 27 are supported by the bottom plate 21a such that the regulation plates face each other in the width direction W and the rack plates are slidable in the left and right directions. Each rack plate meshes with a pinion (not shown) supported by the bottom plate 21a. As a result, the pair of side cursors 27 slide in the opposite direction in synchronization. By sliding the pair of side cursors 27 toward each other to bring the respective regulation plates into contact with both side edges of the sheet placed on the lift plate 23 through the notches 23a of the lift plate 23, It is aligned in the width direction W.

エンドカーソル２９は、本体部２１の底板２１ａの幅方向Ｗの中央に、給送方向Yに沿ってスライド可能に支持されている。エンドカーソル２９を、リフト板２３の切り欠き２３ｂを通って前方に向けてスライドさせて、リフト板２３に載置された用紙の後端縁に当接させることで、用紙が給送方向Ｙに整合される。 The end cursor 29 is supported at the center of the bottom plate 21 a of the main body 21 in the width direction W so as to be slidable along the feeding direction Y. By sliding the end cursor 29 forward through the notch 23b of the lift plate 23 and contacting the trailing edge of the paper placed on the lift plate 23, the paper is fed in the feeding direction Y. Be aligned.

次に、緩衝部材３１について、図１０〜図１２を参照して説明する。図１０及び図１１は緩衝部材を示す斜視図、図１２は緩衝部材を示す断面図である。 Next, the cushioning member 31 will be described with reference to FIGS. 10 to 12. 10 and 11 are perspective views showing the cushioning member, and FIG. 12 is a sectional view showing the cushioning member.

緩衝部材３１は、前壁部２１Ｂの一対のリブ４９に回動可能に支持される回動部材７１と、回動部材７１に相対回転可能に嵌合する支持部材７３と、回動部材７１及び支持部材７３を一対のリブ４９（本体部２１）に対して位置決めする第２の付勢部材としてのダブルトーションバネ７５と、を有している。緩衝部材３１は、前壁部２１Ｂに収容される。 The cushioning member 31 includes a rotating member 71 that is rotatably supported by the pair of ribs 49 of the front wall portion 21B, a supporting member 73 that is relatively rotatably fitted to the rotating member 71, a rotating member 71, and It has a double torsion spring 75 as a second biasing member for positioning the support member 73 with respect to the pair of ribs 49 (main body portion 21). The cushioning member 31 is housed in the front wall portion 21B.

まず、回動部材７１について説明する。回動部材７１は、軸部８１と、当接部８３と、を有している。軸部８１は略円柱形状であり、同軸上に配置される第１円柱部８５及び第２円柱部８７と、両円柱部８５及び８７間の中間部８９と、を有している。軸部８１の両端面には、支軸９１がそれぞれ同軸上に突設されている。第２円柱部８７の長さは、第１円柱部８５よりも短く、第２円柱部８７の外径は、第１円柱部８５よりも大きい。第２円柱部８７には、バネ係止片９３が形成されている。バネ係止片９３は、第２円柱部８７の外周面の端部（支軸９１側の端部）から、軸方向と交差する径方向に突出している。 First, the rotating member 71 will be described. The rotating member 71 has a shaft portion 81 and a contact portion 83. The shaft portion 81 has a substantially columnar shape, and has a first columnar portion 85 and a second columnar portion 87 that are coaxially arranged, and an intermediate portion 89 between the both columnar portions 85 and 87. Support shafts 91 are coaxially projected from both end surfaces of the shaft portion 81. The length of the second column portion 87 is shorter than that of the first column portion 85, and the outer diameter of the second column portion 87 is larger than that of the first column portion 85. A spring locking piece 93 is formed on the second columnar portion 87. The spring locking piece 93 projects from the end of the outer peripheral surface of the second columnar portion 87 (the end on the side of the support shaft 91) in the radial direction intersecting the axial direction.

図１２に示されるように、中間部８９は略四角柱状であり、外周面には、略１／４円弧状に湾曲した湾曲面９５と、湾曲面９５の外周面の接線方向に沿った平坦面９７とが形成されている。 As shown in FIG. 12, the intermediate portion 89 has a substantially quadrangular prism shape, and the outer peripheral surface has a curved surface 95 curved in a substantially ¼ arc shape and a flat surface along the tangential direction of the outer peripheral surface of the curved surface 95. The surface 97 is formed.

当接部８３は、軸部８１の軸方向と交差する方向に長い略直方体形状を有し、長さ方向の略中央部に鈍角に屈曲する屈曲部８３ａが形成されている。当接部８３は、中間部８９の平坦面９７とは反対側の面から、軸部８１の軸方向と交差する方向に突出している。 The contact portion 83 has a substantially rectangular parallelepiped shape that is long in a direction intersecting the axial direction of the shaft portion 81, and has a bent portion 83a that bends at an obtuse angle at a substantially central portion in the length direction. The contact portion 83 projects from the surface of the intermediate portion 89 opposite to the flat surface 97 in a direction intersecting the axial direction of the shaft portion 81.

図１０及び図１１に示されるように、回動部材７１は、軸部８１の両支軸９１が、前壁部２１Ｂ一対のリブ４９に形成された両軸孔５１に軸支されることで、一対のリブ４９（本体部２１）に上下方向に回動可能に支持されている。 As shown in FIGS. 10 and 11, in the rotating member 71, both support shafts 91 of the shaft portion 81 are supported by both shaft holes 51 formed in the pair of ribs 49 of the front wall portion 21B. The pair of ribs 49 (main body 21) are rotatably supported in the vertical direction.

次に、支持部材７３について説明する。支持部材７３は、円筒部１０１と、円筒部１０１の一方の端面に形成された回動部材側係止片１０３と、円筒部１０１の他方の端面に形成された本体側係止片１０５（係止部）と、を有している。円筒部１０１は、回動部材７１の第１円柱部８５に対応する長さと、第１円柱部８５に外嵌可能な内径を有している。 Next, the support member 73 will be described. The support member 73 includes a cylindrical portion 101, a turning member side locking piece 103 formed on one end surface of the cylindrical portion 101, and a main body side locking piece 105 (engagement) formed on the other end surface of the cylindrical portion 101. Stop)). The cylindrical portion 101 has a length corresponding to the first columnar portion 85 of the rotating member 71 and an inner diameter that can be externally fitted to the first columnar portion 85.

回動部材側係止片１０３は、円筒部１０１の一方の端面から、円筒部１０１の軸方向に突出している。回動部材側係止片１０３は、図１２に示されるように、略１／４円筒状の湾曲部１１１と、湾曲部１１１の外周面の接線方向に沿った平板部１１３と、を有している。平板部１１３の周方向の端部には、円筒部１０１の径方向の外側に屈曲する係止片１１５が形成されている。 The rotating member side locking piece 103 projects in the axial direction of the cylindrical portion 101 from one end surface of the cylindrical portion 101. As shown in FIG. 12, the rotating member side locking piece 103 has a substantially quarter-cylindrical curved portion 111 and a flat plate portion 113 along the tangential direction of the outer peripheral surface of the curved portion 111. ing. A locking piece 115 that is bent outward in the radial direction of the cylindrical portion 101 is formed at the circumferential end of the flat plate portion 113.

本体側係止片１０５は、矩形の板片状であり、円筒部１０１の他方の端面から、円筒部１０１の軸方向と交差する方向に突出している。 The main body side locking piece 105 has a rectangular plate piece shape, and protrudes from the other end surface of the cylindrical portion 101 in a direction intersecting the axial direction of the cylindrical portion 101.

円筒部１０１は、回動部材７１の軸部８１の第１円柱部８１ａに外嵌されている。図１２に示されるように、回動部材側係止片１０３の湾曲部１１１の内側の面と平板部１１３の内側の接触面とは、回動部材７１の中間部８９の湾曲面９５と平坦面９７とに、それぞれ当接している。これにより、支持部材７３は回動部材７１に対して一方向には回転するが、他方向への回転が規制されるようになっている。詳細には、平板部１１３の内側の接触面と平坦面９７とは平面同士で接触している一方で、湾曲部１１１の内側の面と湾曲面９５とは円弧状の曲面同士で接触している。このため、回動部材７１は、支持部材７３に対して、湾曲面９５が、回動部材側係止片１０３の平板部１１３へ向かう方向の回転（図１２における反時計回り方向）は可能であるが、湾曲面９５が、回動部材側係止片１０３の平板部１１３とは反対の側へ向かう方向の回転（図１２における時計回り方向）は規制される。 The cylindrical portion 101 is fitted onto the first cylindrical portion 81a of the shaft portion 81 of the rotating member 71. As shown in FIG. 12, the inner surface of the curved portion 111 of the rotating member side locking piece 103 and the inner contact surface of the flat plate portion 113 are flat with the curved surface 95 of the intermediate portion 89 of the rotating member 71. It is in contact with the surface 97, respectively. As a result, the support member 73 rotates in one direction with respect to the rotating member 71, but rotation in the other direction is restricted. Specifically, the inner contact surface of the flat plate portion 113 and the flat surface 97 are in flat contact with each other, while the inner surface of the curved portion 111 and the curved surface 95 are in contact with each other in arcuate curved surfaces. There is. Therefore, the rotating member 71 is rotatable with respect to the supporting member 73 in the direction in which the curved surface 95 faces the flat plate portion 113 of the rotating member side locking piece 103 (counterclockwise direction in FIG. 12 ). However, rotation of the curved surface 95 in the direction toward the side opposite to the flat plate portion 113 of the rotating member side locking piece 103 (clockwise direction in FIG. 12) is restricted.

次に、ダブルトーションバネ７５について説明する。図１０及び図１１に示されるように、ダブルトーションバネ７５は、第１ねじりコイルバネ１２１と、第２ねじりコイルバネ１２３と、両ねじりコイルバネ１２１及び１２３を接続する接続部１２５と、を有している。第１ねじりコイルバネ１２１は、コイル部１３１と第１アーム部１３３とを有している。第２ねじりコイルバネ１２３は、コイル部１４１と第２アーム部１４５とを有している。接続部１２５は、第１ねじりコイルバネ１２１のコイル部１３１と、第２ねじりコイルバネ１２３のコイル部１４１とを接続している。 Next, the double torsion spring 75 will be described. As shown in FIGS. 10 and 11, the double torsion spring 75 has a first torsion coil spring 121, a second torsion coil spring 123, and a connecting portion 125 connecting the both torsion coil springs 121 and 123. .. The first torsion coil spring 121 has a coil portion 131 and a first arm portion 133. The second torsion coil spring 123 has a coil portion 141 and a second arm portion 145. The connecting portion 125 connects the coil portion 131 of the first torsion coil spring 121 and the coil portion 141 of the second torsion coil spring 123.

第１ねじりコイルバネ１２１のコイル部１３１は、支持部材７３の円筒部１０１に外嵌されている。図１１に示されるように、第１ねじりコイルバネ１２１の第１アーム部１３３は、前壁部２１Ｂのリブ４９に形成された凸片５３に係止されている。第２ねじりコイルバネ１２３のコイル部１４１は、回動部材７１の第２円柱部８７に外嵌されている。図１１に示されるように、第２ねじりコイルバネ１２３の第２アーム部１４５は、回動部材７１のバネ係止片９３に係止されている。接続部１２５は、支持部材７３の回動部材側係止片１０３の係止片１１５に係止されている。 The coil portion 131 of the first torsion coil spring 121 is fitted onto the cylindrical portion 101 of the support member 73. As shown in FIG. 11, the first arm portion 133 of the first torsion coil spring 121 is locked to the protruding piece 53 formed on the rib 49 of the front wall portion 21B. The coil portion 141 of the second torsion coil spring 123 is fitted onto the second columnar portion 87 of the rotating member 71. As shown in FIG. 11, the second arm portion 145 of the second torsion coil spring 123 is locked to the spring locking piece 93 of the rotating member 71. The connecting portion 125 is locked to the locking piece 115 of the turning member side locking piece 103 of the support member 73.

図１０〜図１２に示されるように、支持部材７３は、第１ねじりコイルバネ１２１によって、一方のリブ４９に対して基準位置に保持されている。つまり、第１ねじりコイルバネ１２１には、図１２の反時計回り方向（支持部材７３の本体側係止片１０５が上方向へ回動する方向）の付勢力が生じているが、支持部材７３の本体側係止片１０５が一方のリブ４９に形成された凸片５３に下側から当接することで、支持部材７３は回転が規制されて基準位置に保持される。このように、支持部材７３は、一方向（この例では本体側係止片１０５が上方向へ回動する方向）への回転が規制されている。一方で、支持部材７３は反対方向（この例では本体側係止片１０５が下方向へ回動する方向）への回転は可能である。 As shown in FIGS. 10 to 12, the support member 73 is held at the reference position with respect to the one rib 49 by the first torsion coil spring 121. That is, the first torsion coil spring 121 is biased in the counterclockwise direction in FIG. 12 (the direction in which the main body side locking piece 105 of the support member 73 is rotated upward), but The main body side locking piece 105 comes into contact with the convex piece 53 formed on the one rib 49 from below, whereby the rotation of the support member 73 is restricted and the support member 73 is held at the reference position. In this way, the support member 73 is restricted from rotating in one direction (in this example, the main body side locking piece 105 is rotated upward). On the other hand, the support member 73 can rotate in the opposite direction (in this example, the main body side locking piece 105 rotates downward).

回動部材７１は、第２ねじりコイルバネ１２３によって、支持部材７３に対して基準位置に保持されている。つまり、第２ねじりコイルバネ１２３には、図１２の時計回り方向（回動部材７１の当接部８３が下方向へ回動する方向）への付勢力が生じているが、前述のように、回動部材７１の支持部材７３に対する回転（図１２の時計回り方向）が規制されることで、回動部材７１の回転が規制されて基準位置に保持されている。基準位置において、当接部８３は、切り欠き４７から給送方向Ｙの下流側にほぼ水平に延びて、当接部８３の先端が、リフト板２３の突片６１の回動軌跡に干渉している。ただし、当接部８３が基準位置から上方向又は下方向に回動すると、当接部８３の先端は、リフト板２３の突片６１の回動軌跡から離間しり。また、前述のように、回動部材７１は、支持部材７３に対して一方向（この例では図１２の反時計回り方向、当接部８３が上方向へ回動する方向）へは回転可能であるが、反対方向（この例では図１２の時計回り方向、当接部８３が下方向へ回動する方向）への回転は規制される。 The rotating member 71 is held at the reference position with respect to the supporting member 73 by the second torsion coil spring 123. That is, the second torsion coil spring 123 is biased in the clockwise direction of FIG. 12 (the direction in which the contact portion 83 of the rotating member 71 is rotated downward), but as described above, By restricting the rotation of the rotating member 71 with respect to the support member 73 (clockwise direction in FIG. 12), the rotation of the rotating member 71 is restricted and held at the reference position. At the reference position, the contact portion 83 extends substantially horizontally from the notch 47 to the downstream side in the feeding direction Y, and the tip of the contact portion 83 interferes with the rotation locus of the protrusion 61 of the lift plate 23. ing. However, when the contact portion 83 rotates upward or downward from the reference position, the tip of the contact portion 83 separates from the rotation trajectory of the protrusion 61 of the lift plate 23. Further, as described above, the rotating member 71 is rotatable in one direction with respect to the support member 73 (in this example, the counterclockwise direction in FIG. 12, the contact portion 83 is rotated upward). However, rotation in the opposite direction (in this example, the clockwise direction in FIG. 12, the direction in which the contact portion 83 rotates downward) is restricted.

次に、給紙装置１１について、図４等を参照して説明する。給紙装置１１は、給紙カセット５から用紙を送り出すピックアップローラー１５１と、給紙ローラー１５３と、を備えている。給紙装置１１は、筐体３のカセット収容部７の前端部の上方に配置されている。 Next, the sheet feeding device 11 will be described with reference to FIG. The sheet feeding device 11 includes a pickup roller 151 that feeds a sheet from the sheet feeding cassette 5, and a sheet feeding roller 153. The paper feeding device 11 is arranged above the front end portion of the cassette housing portion 7 of the housing 3.

ピックアップローラー１５１と給紙ローラー１５３とは、給送方向Ｙに沿って順に配置されて、それぞれ回転軸を中心として回転可能に支持されている。給紙ローラー１５３の回転軸には、ギア等を介して駆動モーターが接続している。ピックアップローラー１５１の回転軸と給紙ローラー１５３の回転軸との間にはギアが介装されている。給紙ローラー１５３の回転軸が回転することで、ピックアップローラー１５１が回転軸を中心として給紙ローラー１５３と同じ方向に回転する。 The pickup roller 151 and the paper feed roller 153 are sequentially arranged along the feeding direction Y, and are rotatably supported around a rotation axis. A drive motor is connected to the rotation shaft of the paper feed roller 153 via a gear or the like. A gear is interposed between the rotation shaft of the pickup roller 151 and the rotation shaft of the paper feed roller 153. When the rotation shaft of the paper feed roller 153 rotates, the pickup roller 151 rotates in the same direction as the paper feed roller 153 around the rotation shaft.

上記構成を有する給紙カセット５からの給紙動作について、図４〜図９と、図１０〜図１４とを参照して説明する。図１３及び図１４は、緩衝部材を示す断面図である。各図においてリフト板に載置された用紙は図示省略されている。 A paper feeding operation from the paper feeding cassette 5 having the above configuration will be described with reference to FIGS. 4 to 9 and FIGS. 13 and 14 are cross-sectional views showing the cushioning member. In each drawing, the paper placed on the lift plate is not shown.

最初に、給紙カセット５をカセット収容部７から引き出し、本体部２１の用紙収容部２１Ａに用紙をセットする。まず、図４に示されるように、リフト板２３を下降させて、リフト板２３とロック板４１とを係合させ、リフト板２３を下降位置で上昇不能にロックする。リフト板２３の突片６１は、前壁部２１Ｂに収容される。次に、下降したリフト板２３に用紙を載置する。この際、用紙の先端を、前板２１ｂの先端壁２１ｄに当てて先端を揃える。その後、一対のサイドカーソル２７をスライドさせて用紙の幅方向Ｗの両側縁に当接させる。また、エンドカーソル２９をスライドさせて用紙の後端縁に当接させる。このように用紙をセットした後、給紙カセット５を、開口７ａを通してカセット収容部７に装着する。 First, the paper feed cassette 5 is pulled out from the cassette housing portion 7, and the paper is set in the paper housing portion 21A of the main body portion 21. First, as shown in FIG. 4, the lift plate 23 is lowered, the lift plate 23 and the lock plate 41 are engaged with each other, and the lift plate 23 is locked so as not to be lifted at the lowered position. The protrusion 61 of the lift plate 23 is housed in the front wall portion 21B. Next, the sheet is placed on the lift plate 23 that has descended. At this time, the leading edge of the paper is brought into contact with the leading edge wall 21d of the front plate 21b to align the leading edges. After that, the pair of side cursors 27 are slid to abut both side edges of the sheet in the width direction W. Further, the end cursor 29 is slid so that it comes into contact with the trailing edge of the sheet. After the sheets are set in this way, the sheet feeding cassette 5 is attached to the cassette housing portion 7 through the opening 7a.

すると、前述のように、給紙カセット５の装着が完了する前にリフト板２３とロック板４１との係合が解除されてリフト板２３が上昇可能となり、リフト板２３がボトムバネ２５で付勢されて上昇する。この際、リフト板２３は、載置された用紙の最上位の用紙がピックアップローラー１５１に当接する上昇位置（上限位置よりも下方）に回動する。 Then, as described above, before the mounting of the paper feed cassette 5 is completed, the engagement between the lift plate 23 and the lock plate 41 is released, and the lift plate 23 can be raised, and the lift plate 23 is biased by the bottom spring 25. Being lifted. At this time, the lift plate 23 rotates to a raised position (below the upper limit position) where the uppermost sheet of the placed sheets contacts the pickup roller 151.

載置された用紙の枚数が少ない場合（例えば、サイズの異なる用紙を収容する場合、ジャム処理の場合等）、図５に示されるように、リフト板２３の上昇に伴い、２つの突片６１は、前壁部２１Ｂ内において切り欠き４７を通って上昇し、緩衝部材３１の２つの当接部８３に下方から当接する。その後、図６に示されるように、当接部８３は突片６１で押し上げられて上方へ回動し、やがて突片６１から離間する。その後、図７に示されるように、当接部８３は基準位置に回動する。なお、用紙が満杯程度に載置された場合は、リフト板２３は緩衝部材３１に当接するまで上昇しないこともある。 When the number of placed sheets is small (for example, when sheets of different sizes are accommodated, when jamming is performed, etc.), as shown in FIG. Rises through the notch 47 in the front wall portion 21B and abuts the two abutting portions 83 of the cushioning member 31 from below. After that, as shown in FIG. 6, the contact portion 83 is pushed up by the projecting piece 61 and pivots upward, and eventually separates from the projecting piece 61. Then, as shown in FIG. 7, the contact portion 83 rotates to the reference position. When the sheet is fully loaded, the lift plate 23 may not rise until it comes into contact with the cushioning member 31.

リフト板２３が上昇する際の緩衝部材３１の動作について、図１２及び図１３を主に参照して説明する。各突片６１が各当接部８３に下方から当接すると（図５参照）、リフト板２３は減速されて上昇する。ここで、支持部材７３は、前述のように本体側係止片１０５が凸片５３に係止されて上方向への回転が規制されている。一方、回動部材７１は、支持部材７３に対して一方向（図１２の反時計回り方向、当接部８３が上方向へ回動する方向）へは回転可能であるので、図１３に示されるように、当接部８３を含む回動部材７１が、支持部材７３に対して回転して、第２ねじりコイルばね１２３の付勢力に抗して上方向へ回動する（図６参照）。この第２ねじりコイルバネ１２３の付勢力に抗する力によって、ボトムバネ２５の付勢力が緩衝されて、リフト板２３は、緩衝部材３１に当接する前までの速度よりも遅い速度で上昇する。 The operation of the cushioning member 31 when the lift plate 23 rises will be described mainly with reference to FIGS. 12 and 13. When each protrusion 61 contacts each contact portion 83 from below (see FIG. 5), the lift plate 23 is decelerated and moves up. Here, in the support member 73, the main body side locking piece 105 is locked to the convex piece 53 as described above, and the upward rotation is restricted. On the other hand, since the rotating member 71 is rotatable in one direction with respect to the supporting member 73 (counterclockwise direction in FIG. 12, the direction in which the contact portion 83 rotates upward), it is shown in FIG. As described above, the rotating member 71 including the contact portion 83 rotates with respect to the supporting member 73 and rotates upward against the biasing force of the second torsion coil spring 123 (see FIG. 6). .. The urging force of the bottom spring 25 is buffered by the force that opposes the urging force of the second torsion coil spring 123, and the lift plate 23 rises at a speed slower than the speed before contacting the buffer member 31.

さらにリフト板２３が上昇すると、リフト板２３の突片６１が緩衝部材３１の当接部８３から離間する。すると、リフト板２３はボトムバネ２５で付勢されて、リフト板２３に載置された用紙の最上位の用紙がピックアップローラー１５１に当接する（図７参照）。しかし、リフト板２３はピックアップローラー１５１に近接する高さまで上昇している、言い換えると、ボトムバネ２５はほぼ自由長に近い長さまで伸長しているので、リフト板２３に作用するボトムバネ２５の付勢力は小さくなる。つまり、図６に示されるボトムバネ２５の伸長長さと図７に示されるボトムバネ２５の伸長長さの差だけの付勢力で、リフト板２３が上昇する。このため、リフト板２３に載置された用紙の最上位の用紙がピックアップローラー１５１に当接した際の衝撃は小さくなる。なお、リフト板２３の突片６１は、切り欠き４７を通って前壁部２１Ｂから上方に離間する。 When the lift plate 23 further rises, the protrusion 61 of the lift plate 23 separates from the contact portion 83 of the buffer member 31. Then, the lift plate 23 is biased by the bottom spring 25, and the uppermost sheet of the sheets placed on the lift plate 23 comes into contact with the pickup roller 151 (see FIG. 7). However, the lift plate 23 has risen to a height close to the pickup roller 151, in other words, since the bottom spring 25 extends to a length close to a substantially free length, the urging force of the bottom spring 25 acting on the lift plate 23 is Get smaller. That is, the lift plate 23 rises by the urging force corresponding to the difference between the extension length of the bottom spring 25 shown in FIG. 6 and the extension length of the bottom spring 25 shown in FIG. Therefore, the impact when the uppermost sheet of the sheets placed on the lift plate 23 comes into contact with the pickup roller 151 is small. The protrusion 61 of the lift plate 23 passes through the notch 47 and is separated upward from the front wall portion 21B.

リフト板２３の突片６１が緩衝部材３１の当接部８３から離間した後、回動部材７１は第２ねじりコイルバネ１２３で付勢されて支持部材７３に対して回転し、基準位置に回動する（図１２参照）。なお、通常の給紙動作によって載置される用紙の枚数が減ると、リフト板２３はボトムバネ２５で付勢されて上昇して、最上位の用紙をピックアップローラー１５１に当接させる。この際のリフト板２３の上昇時にも、リフト板２３は緩衝部材３１に当接する。 After the protrusion 61 of the lift plate 23 is separated from the contact portion 83 of the cushioning member 31, the rotating member 71 is biased by the second torsion coil spring 123 to rotate with respect to the supporting member 73, and rotates to the reference position. (See FIG. 12). It should be noted that when the number of sheets to be placed decreases due to the normal sheet feeding operation, the lift plate 23 is urged by the bottom spring 25 to move upward and bring the uppermost sheet into contact with the pickup roller 151. Even when the lift plate 23 is raised at this time, the lift plate 23 contacts the cushioning member 31.

給紙カセット５に用紙を補充する際には、給紙カセット５をカセット収容部７から引き出し、リフト板２３を手で押し下げる。リフト板２３が本体部２１の底板２１ａに接するまで押し下げると、前述のように、係合片６５がロック板４１の係合部４１ｂを下方に押圧し、付勢部材の付勢力に抗してロック板４１が内方向に移動する。リフト板２３がさらに下降して係合片６５が係合部４１ｂから下方に離間すると、ロック板４１は付勢部材で付勢されて外方向にスライドして、係合部４１ｂが係合片６５に係合する。これにより、リフト板２３とロック板４１とが係合する。 When replenishing the paper feed cassette 5 with paper, the paper feed cassette 5 is pulled out from the cassette housing portion 7 and the lift plate 23 is pushed down by hand. When the lift plate 23 is pushed down until it comes into contact with the bottom plate 21a of the main body portion 21, as described above, the engagement piece 65 pushes the engagement portion 41b of the lock plate 41 downward, and resists the biasing force of the biasing member. The lock plate 41 moves inward. When the lift plate 23 further descends and the engaging piece 65 is separated downward from the engaging portion 41b, the lock plate 41 is biased by the biasing member and slides outward, so that the engaging portion 41b moves. Engage 65. As a result, the lift plate 23 and the lock plate 41 are engaged with each other.

リフト板２３を下降させる際、図８に示されるように、リフト板２３の２つの突片６１は、前壁部２１Ｂ内において、緩衝部材３１の２つの当接部８３に上方からから当接する。これにより、当接部８３は突片６１で押し下げられて、図９に示されるように、当接部８３は下方へ回動する。当接部８３が突片６１から離間した後、図４に示されるように、緩衝部材３１は基準位置に回動する。 When lowering the lift plate 23, as shown in FIG. 8, the two projecting pieces 61 of the lift plate 23 come into contact with the two contact portions 83 of the buffer member 31 from above in the front wall portion 21B. .. As a result, the contact portion 83 is pushed down by the projecting piece 61, and the contact portion 83 pivots downward as shown in FIG. After the contact portion 83 separates from the protrusion 61, the cushioning member 31 rotates to the reference position, as shown in FIG.

リフト板２３を下降させる際の緩衝部材３１の動作について、図１２及び図１４を主に参照して説明する。各突片６１が各当接部８３に上方から当接する（図８参照）と、回動部材７１は下方向へ回動する。ここで、回動部材７１は、支持部材７３に対して他方向（図１２の時計回り方向、言い換えると、当接部８３が下方向へ回動する方向）への回転が規制されているので、回動部材７１と共に支持部材７３が第１ねじりコイルバネ１２１の付勢力に抗して回転する。つまり、緩衝部材３１は、回動部材７１と支持部材７３とが基準位置における位置関係を保ったままで下方向へ回動する。なお、第２ねじりコイルバネ１２３には力が作用していない。 The operation of the buffer member 31 when lowering the lift plate 23 will be described mainly with reference to FIGS. 12 and 14. When each projecting piece 61 comes into contact with each contacting portion 83 from above (see FIG. 8), the rotating member 71 rotates downward. Here, the rotation member 71 is restricted from rotating in the other direction (clockwise direction in FIG. 12, in other words, the direction in which the contact portion 83 rotates downward) with respect to the support member 73. The support member 73 rotates together with the rotating member 71 against the biasing force of the first torsion coil spring 121. That is, the cushioning member 31 rotates downward while the rotation member 71 and the support member 73 maintain the positional relationship at the reference position. Note that no force acts on the second torsion coil spring 123.

リフト板２３が下降して、突片６１が当接部８３から離間すると、支持部材７３は第１ねじりコイルバネ１２１で付勢されて、緩衝部材３１は、回動部材７１と支持部材７３とが基準位置における位置関係を保ったままで基準位置に回動する。 When the lift plate 23 descends and the projecting piece 61 separates from the contact portion 83, the support member 73 is urged by the first torsion coil spring 121, and the cushioning member 31 separates the rotating member 71 and the support member 73. It rotates to the reference position while maintaining the positional relationship at the reference position.

上記説明したように、本発明によれば、ボトムバネ２５で付勢されたリフト板２３は、一旦緩衝部材３１に当接した後で、最上位の用紙がピックアップローラー１５１に当接するまで上昇する。このように、ボトムバネ２５の付勢力が緩衝されて、リフト板２３の上昇速度が減速されるので、ピックアップローラー１５１がリフト板２３から受ける衝撃を緩和できる。したがって、リフト板２３に載置された用紙の枚数が少ない場合にも、ピックアップローラー１５１を一定の位置で用紙に当接させることができ、ピックアップローラー１５１によって適正に用紙を搬送することができる。さらに、ピックアップローラー１５１にリフト板２３が当接する際の騒音の発生も抑制できる。さらに、ピックアップローラー１５１の耐久性を延ばすことができる。 As described above, according to the present invention, the lift plate 23 biased by the bottom spring 25 once abuts on the cushioning member 31, and then rises until the uppermost sheet abuts on the pickup roller 151. In this way, the urging force of the bottom spring 25 is buffered and the rising speed of the lift plate 23 is reduced, so that the impact that the pickup roller 151 receives from the lift plate 23 can be alleviated. Therefore, even when the number of sheets of paper placed on the lift plate 23 is small, the pickup roller 151 can be brought into contact with the sheet of paper at a fixed position, and the sheet of paper can be properly conveyed by the pickup roller 151. Further, it is possible to suppress the generation of noise when the lift plate 23 contacts the pickup roller 151. Furthermore, the durability of the pickup roller 151 can be extended.

また、リフト板２３に直接当接する回動部材７１は、下方向へ回動した際には第２ねじりコイルバネ１２３によって基準位置に付勢され、上方向へ回動した際には支持部材７３を介して第１ねじりコイルバネ１２１によって基準位置に付勢されるようになっている。このように、緩衝部材３１は、リフト板２３が昇降する際に一旦当接して上下方向回動した後で、リフト板２３から離間すると基準位置に自動的に回動するので、リフト板２３の昇降動作を阻害しない。 Further, the rotating member 71 that directly abuts the lift plate 23 is urged to the reference position by the second torsion coil spring 123 when rotating downward, and the supporting member 73 when moving upward. The first torsion coil spring 121 is urged to the reference position via the above. In this manner, the cushioning member 31 once abuts when the lift plate 23 moves up and down, rotates in the up-down direction, and then automatically rotates to the reference position when separated from the lift plate 23. Does not hinder the lifting operation.

なお、リフト板２３の上昇時に、回動部材７１が支持部材７３と基準位置における位置関係を保ったままで上方に回動し、リフト板２３の下降時に、回動部材７１が支持部材７３に対して下方に回動するようにしてもよい。 It should be noted that when the lift plate 23 rises, the rotating member 71 rotates upward while maintaining the positional relationship with the support member 73 at the reference position, and when the lift plate 23 descends, the rotating member 71 moves relative to the support member 73. You may make it rotate downwards.

また、緩衝部材３１を、回動部材７１と支持部材７３とダブルトーションバネ７５の３つの部材からなる簡易な構成とすることができる。 Further, the cushioning member 31 can have a simple structure including three members of the rotating member 71, the supporting member 73, and the double torsion spring 75.

さらに、緩衝部材３１は、用紙収容部２１Ａとは隔離された前壁部２１Ｂに収容されているので、用紙を収容する作業に干渉しない。 Further, since the buffer member 31 is housed in the front wall portion 21B that is separated from the paper housing portion 21A, it does not interfere with the work for housing the paper.

さらに、上記した本発明の実施形態の説明は、本発明に係る画像形成装置及び給紙カセットにおける好適な実施の形態を説明しているため、技術的に好ましい種々の限定を付している場合もあるが、本発明の技術範囲は、特に本発明を限定する記載がない限り、これらの態様に限定されるものではない。 Further, since the above description of the embodiments of the present invention describes the preferred embodiments of the image forming apparatus and the sheet feeding cassette according to the present invention, various technically preferable limitations are given. However, the technical scope of the present invention is not limited to these embodiments unless otherwise specified.

１プリンター（画像形成装置）
５給紙カセット
７カセット収容部
９給紙装置
２１本体部
２１ｂ前板
２１Ｂ前壁部
２３リフト板
２５ボトムバネ（第１の付勢部材）
３１緩衝部材
７１回動部材
７３支持部材
７５ダブルトーションバネ（第２の付勢部材）
８１軸部
８３当接部
１０１円筒部
１０５本体側係止片（係止部）
１２１第１ねじりコイルバネ
１２３第２ねじりコイルバネ
１５１ピックアップローラー 1 Printer (image forming device)
5 Paper Feed Cassette 7 Cassette Housing 9 Paper Feed Device 21 Main Body 21b Front Plate 21B Front Wall 23 Lift Plate 25 Bottom Spring (First Biasing Member)
31 cushioning member 71 rotating member 73 support member 75 double torsion spring (second biasing member)
81 Shaft part 83 Abutment part 101 Cylindrical part 105 Main body side locking piece (locking part)
121 first torsion coil spring 123 second torsion coil spring 151 pickup roller

Claims

A paper feed cassette, which is mounted in a cassette housing unit having a pickup roller and stores paper fed in a predetermined feeding direction by the pickup roller,
A main body for accommodating the paper,
Between the lower position where the paper is placed on the main body portion and the ascending position where the placed paper comes into contact with the pickup roller, the upstream end in the feeding direction is a fulcrum. A lift plate rotatably supported,
A first urging member that urges the lift plate from the lowered position to the raised position by being attached to the cassette housing portion;
The lift plate is supported at a reference position that interferes with the rotation trajectory of the leading edge of the lift plate that rotates between the lowered position and the raised position, and is rotated by the first biasing member. A cushioning member for reducing the moving speed,
The cushioning member,
The lift plate is urged by the first urging member to move from the lowered position to the raised position and is brought into contact with the lift plate to rotate upward from the reference position while applying a predetermined load to the lift plate. After the lift plate has passed, it is rotated downward and held at the reference position,
When the lift plate rotates from the raised position to the lowered position, it abuts on the lift plate and rotates downward, and after the lift plate passes, it rotates upward and is held at the reference position. A paper feed cassette characterized by being processed.

The main body portion has a front wall portion, which is partitioned by a front plate and accommodates the cushioning member, at an end portion on the downstream side in the feeding direction,
The front plate has a notch formed along the vertical direction,
The lift plate has a protruding piece protruding from the tip edge,
2. The paper feed cassette according to claim 1, wherein when the lift plate rotates, the protruding piece comes into contact with the buffer member when passing through the notch.

The cushioning member,
A rotating member that is rotatably supported in the up-down direction by the main body, and is in contact with the lift plate when the lift plate rotates.
A support member that rotates relative to the rotating member,
A second urging member that urges the support member to the reference position with respect to the main body, and urges the rotating member to the reference position with respect to the support member. The paper feed cassette according to claim 1 or 2, characterized in that:

The rotating member is
A shaft portion rotatably supported by the main body portion in a vertical direction; and a contact portion with which the lift plate abuts when the lift plate rotates,
The support member is
A cylindrical portion that is fitted onto the shaft portion and rotates with respect to the shaft portion; and a locking portion that is locked to the main body portion,
The second biasing member is
A first torsion coil spring for positioning the support member with respect to the main body, and a second torsion coil spring for positioning the rotating member with respect to the support member,
When the lift plate rotates upward and comes into contact with the contact portion from below, rotation of the support member from the reference position is restricted by the engagement portion being engaged with the main body portion. On the other hand, the rotating member rotates upward with respect to the supporting member against the biasing force of the second torsion coil spring,
After that, when the contact portion is separated from the lift plate, the rotating member is biased by the second torsion coil spring to rotate to the reference position,
When the lift plate rotates downward and comes into contact with the contact portion from above, the rotating member rotates downward, and the supporting member resists the biasing force of the first torsion coil spring. Rotate from the reference position,
4. The paper feeding cassette according to claim 3, wherein when the contact portion is separated from the lift plate, the support member is biased by the first torsion coil spring to rotate to the reference position.

A sheet feeding cassette according to any one of claims 1 to 4,
An image forming apparatus, comprising: an image forming unit that forms an image on a sheet fed by the pickup roller from the sheet feeding cassette mounted in the cassette housing unit.