JP2012188233A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus configured such that the position of an extension tray can be freely changed, and also, the extension tray can be automatically stored, thereby, the operational convenience of the user can be enhanced.SOLUTION: The image forming apparatus includes: a cover tray 7 which covers the opening of a housing, also, which is rotatable about a horizontal axis with reference to the housing, and on which paper sheets can be placed in the state where the opening is kept open; the extension tray 9 provided on the cover tray 7, and which can be displaced between a storage position and an extension position in a direction nearly parallel to the placing surface 7B for placing the paper sheets; a coil spring 11 for always energizing the extension tray 9 toward the storage position; a locking mechanism for controlling, in a plurality of steps, the movement of the extension tray 9 in a direction energized by the coil spring 11; and a locking release mechanism for releasing the control of the locking mechanism in conjunction with the operation of closing the cover tray 7.

Description

  The present invention relates to an image forming apparatus.

  For example, in the image forming apparatus described in Patent Document 1, a paper feed tray on which paper can be placed when rotated and opened with respect to the apparatus housing is provided on the side surface of the apparatus housing, and the paper feed tray is rotated. An extension tray that expands and contracts in a direction perpendicular to the rotation axis of the paper feed tray in conjunction with the operation is provided in the paper feed tray.

JP 2010-180048 A

  However, in the image forming apparatus described in Patent Document 1, the extension tray is always extended to the same position in conjunction with the rotation of the paper feed tray. There is a problem that the usability is not good.

  SUMMARY OF THE INVENTION In view of the above, the present invention provides an image forming apparatus that can freely change the position of an extension tray and can improve the user-friendliness by automatically enabling the extension tray to be stored. The purpose is to do.

  In order to achieve the above object, according to the present invention, an image forming unit (5) for forming an image on a sheet and an opening for feeding the sheet to the image forming unit (5) are provided. The device housing (3) provided with (3A) and the opening (3A) are covered, and the device housing (3) is rotatable around an axis that is horizontal to the device housing (3), and the opening (3A) A cover tray (7) capable of placing paper in an open state, and a storage position provided in the cover tray (7) in a direction substantially parallel to the placement surface (7B) on which the paper is placed. An extension tray (9) that is displaceable between the extension tray and the extension position, a first elastic member (11) that constantly biases the extension tray (9) toward the storage position, and an elastic member of the extension tray (9) ( 11) A lock mechanism (9B, 13, 13) that restricts movement in the urging direction in multiple stages. 17) and a lock release mechanism (15, 15B, 3B) for releasing the restriction by the lock mechanism (9B, 13, 13A, 17) in conjunction with the operation of closing the cover tray (7). Features.

  Accordingly, in the present invention, when the extension tray (9) is displaced to the extension position side, the user manually performs the extension tray (9), so that the user can extend the extension tray by an amount necessary for the paper size used by the user. (9) can be displaced toward the extended position.

  Further, since the extension tray (9) displaced to the extension position side is displaced to the accommodation position in conjunction with the operation of closing the cover tray (7) by the user, the user separately moves the extension tray (9) to the accommodation position side. Therefore, it is not necessary to perform an operation of displacing, and user convenience is improved.

  Incidentally, the reference numerals in parentheses for each of the above means are examples showing the correspondence with the specific means described in the embodiments described later, and the present invention is indicated by the reference numerals in the parentheses of the above respective means. It is not limited to specific means.

1 is a central sectional view of an image forming apparatus according to an embodiment of the present invention. 1 is a perspective view of an image forming apparatus according to an embodiment of the present invention. It is a perspective view of the cover tray 7 of the open state which concerns on embodiment of this invention. It is a top view of the cover tray 7 of the open state which concerns on embodiment of this invention. (A) is the A section enlarged view of FIG. 3, (b) is AA sectional drawing of Fig.5 (a). (A)-(c) is a figure which shows the engagement state change of the lock nail | claw 13A and the rack 9B in the AA cross section of FIG. 4, (d)-(f) is in the BB cross section of FIG. It is a figure which shows the action | operation of the contact protrusion part 15B, the cam protrusion part 3B, and the cover tray 7. FIG. (A) is the B section enlarged view of FIG. 3, (b) is the C section enlarged view of FIG. It is a top view of the cover tray 7 of the open state which concerns on 2nd Embodiment of this invention. (A) is a perspective view of the rotating shaft 50 which concerns on 2nd Embodiment of this invention, (b) is a perspective view of the rotation operating rod 15 which concerns on 2nd Embodiment of this invention, (c) is rotation. FIG. 6 is a perspective view showing a state in which a shaft 50 and a rotary operation rod 15 are engaged. (A)-(c) is a figure which shows the engagement state change of the lock nail | claw 13A and the rack 9B in the AA cross section of FIG. 8, (d)-(f) is in the BB cross section of FIG. It is a figure which shows the action | operation of protrusion part 13D, 15D and the cover tray 7. FIG.

In the present embodiment, the present invention is applied to a monochrome image forming apparatus, and the present embodiment will be described below with reference to the drawings.
(First embodiment)
1. Outline of Image Forming Apparatus As shown in FIG. 1, an image of an electrophotographic system in which an image is formed on a recording sheet (hereinafter referred to as a sheet) such as a recording sheet or an OHP sheet is provided in a housing 3 of the image forming apparatus 1. The forming unit 5 is accommodated, and the image forming unit 5 forms an image on the sheet by transferring the developer image (toner image) carried on the photosensitive drum 5A to the sheet.

  Further, as shown in FIG. 2, an opening 3 </ b> A for feeding paper to the image forming unit 5 is provided on one end side in the horizontal direction of the housing 3 (front side in the present embodiment). The cover tray 7 covering the opening 3A is between the position where the opening 3A is opened and the position where the opening 3A is opened with the rotation shaft 7A set on the lower end side of the housing 3 as the swing center. Can be swung and rotated.

  Hereinafter, the state in which the opening 3A is opened (the state indicated by the two-dot chain line in FIG. 1) is referred to as the state in which the cover tray 7B is opened, and the state in which the opening 3A is covered (the state indicated by the solid line in FIG. 1). ) Is a state in which the cover tray 7 is closed. Incidentally, the rotating shaft 7A is set so that the axial direction thereof coincides with the horizontal direction orthogonal to the opening direction of the opening 3A (the front-rear direction in the present embodiment).

  In addition, on the upper surface of the cover tray 7 in the opened state, a placement surface 7B for placing paper fed to the image forming unit 5 is set. The placement surface 7B has a rotation axis. An extension tray 9 that can be displaced in a direction away from 7 </ b> A is provided in the center of the cover tray 7 in the axial direction.

  The extension tray 9 is configured in a band plate shape extending in the moving direction, and a storage position where the entire extension tray 9 overlaps the cover tray 7 (for example, a position indicated by a solid line in FIG. 1), and the extension tray 9. Can move in parallel with respect to the cover tray 7 (mounting surface 7B) with respect to an extended position (for example, a position indicated by a two-dot chain line in FIG. 1) that is displaced from the cover tray 7.

  As shown in FIG. 1, the extension tray 9 protrudes in a direction rising at a right angle from the mounting surface 7B, and is fed, at the end on the remote side, which is the end on the side away from the rotating shaft 7A. A rear guide surface 9A is provided that can come into contact with the rear end in the paper feeding direction.

  On the other hand, at the end of the storage position side opposite to the separation side of the extension tray 9, an elastic force that displaces the extension tray 9 toward the rotating shaft 7A is applied to the extension tray 9, as shown in FIGS. A coil spring 11 to be actuated is provided. One end of the coil spring 11 in the axial direction is connected to the end of the extension tray 9 on the storage position side, and the other end in the axial direction is connected to the rotating shaft 7A side of the cover tray 7. ing. That is, the extension tray 9 is always biased toward the accommodation position by the coil spring 11.

2. Lock mechanism and lock release mechanism The lock mechanism is a mechanism for restricting the movement of the extension tray 9 by the coil spring 11 in a plurality of stages, and the lock release mechanism is a mechanism for releasing the restriction by the lock mechanism. Details will be described below.

  As shown in FIGS. 5 (a) to 5 (b), on the one end side in the width direction that is perpendicular to the displacement direction of the extension tray 9 and in the horizontal direction, the separation side is along the displacement direction of the extension tray 9. A rack 9B extending from the storage position side to the storage position side is integrally formed. A plurality of convex portions and concave portions are formed in the rack 9 </ b> B along the displacement direction of the extension tray 9.

  In the cover tray 7, the position corresponding to the rack 9 </ b> B and facing the extension tray 9 extends from the extension tray 9 toward the rotating shaft 7 </ b> A in parallel with the displacement direction of the extension tray 9 as shown in FIG. 4. A lock operation bar 13 is provided, and this lock operation bar 13 is assembled to the cover tray 7 so as to be able to rotate with its extending direction as the rotation center axis.

  Further, on the extension tray 9 side in the extending direction of the lock operating rod 13, as shown in FIGS. 5 (a) to 5 (b), there is a lock claw 13A that forms an engaging projection that can be engaged with the rack 9B. In this embodiment, the lock claw 13A and the lock operation rod 13 are integrally formed of resin.

  For this reason, as shown in FIGS. 6A to 6C, the lock claw 13A is engaged with the rack 9B in conjunction with the rotation of the lock operation bar 13 (at the engagement position (FIG. 6A). Position) and the disengaged position (the position shown in FIG. 6B or 6C) where the engagement is released.

  That is, the lock claw 13A engages with the convex portion or the concave portion of the rack 9B, thereby restricting the extension tray 9 from moving toward the accommodation position against the elastic force of the coil spring 11. On the other hand, when the lock claw 13A is in the release position, the extension tray 9 is moved to the accommodation position by the elastic force of the coil spring 11, and the state where the extension tray 9 is in the accommodation position is maintained.

  Further, as shown in FIG. 7A, a bevel gear meshing with a bevel gear 15A provided at one end in the longitudinal direction of a rotation operation rod 15 to be described later is provided at the end of the rotation shaft 7A in the extending direction of the lock operation rod 13. 13B is provided. The lock operation rod 13 and the rotation operation rod 15 are connected via bevel gears 13B and 15A, and the rotation of the cover tray 7 in the closing direction is transmitted to the lock operation rod 13 by the bevel gears 13B and 15A.

As shown in FIG. 4, the rotation operation rod 15 is a rotation operation member that extends in a direction parallel to the rotation axis of the cover tray 7 and is rotatably supported by the cover tray 7.
Then, on the other end in the longitudinal direction of the rotation operation rod 15, as shown in FIG. 7B, the contact protrusion 15B protruding toward the cam protrusion 3B provided on the apparatus main body (housing 3) side. Are integrally formed. As shown in FIGS. 6 (d) to 6 (f), the contact protrusion 15 </ b> B suppresses the rotation of the rotation operation rod 15 with respect to the closing operation of the cover tray 7.

  Further, as shown in FIG. 7B, the rotation operation rod 15 is provided with an engagement holding spring 17 that applies a rotation force to the rotation operation rod 15. The direction is a direction for maintaining the engaged state between the rack 9B and the lock claw 13A. That is, the engagement holding spring 17 is opposite to the rotation direction of the cover tray 7 when it is opened to maintain the engagement state between the lock claw 13A and the rack 9B via the rotation operation rod 15 and the lock operation rod 13. A rotational force is applied to the rotary operation rod 15.

3. Operation of lock mechanism and unlock mechanism <Lock (regulation) operation>
When the lock claw 13A and the rack 9B are engaged, as described above, the extension tray 9 is restricted from moving toward the accommodation position against the elastic force of the coil spring 11, so that the extension tray 9 is not displaced.

  By the way, the surface of the lock claw 13A on the rack 9B side and the convex or concave surface of the rack 9B on the lock claw 13A side are both configured with a smooth curved surface, so that the cover tray 7 is stored in an open state. When the user applies an operating force to the extension tray 9 toward the position or the extended position, the lock claw 13A is displaced so as to ride on the convex portion of the rack 9B, and the engagement between the lock claw 13A and the rack 9B is released and the extension is extended. The tray 9 is displaced in the direction of the operation force.

  However, since the force for maintaining the engaged state is always applied to the lock claw 13A from the engagement holding spring 17, when the operation force from the user disappears, the lock claw 13A and the rack 9B are immediately engaged. In this state, the movement of the extension tray 9 by the coil spring 11 is restricted in a plurality of stages.

<Lock (regulation) release operation>
When the cover tray 7 rotates from the open state to the closed state, as shown in FIGS. 6D to 6F, the contact protrusion 15B and the cam protrusion 3B are in contact with each other. Therefore, the rotation operation rod 15 cannot rotate like the cover tray 7. For this reason, since the rotation angle of the rotation operation rod 15 is smaller than the rotation angle of the cover tray 7, the rotation operation rod 15 is rotated relative to the cover tray 7.

  That is, when the cover tray 7 is opened, the contact protrusion 15B is substantially parallel to the cover tray 7 (see FIG. 6D). In this state, the lock claw 13A is engaged with the rack 9B. (See FIG. 6A).

  Even if the cover tray 7 is rotated approximately 90 degrees from the opened state and the cover tray 7 is closed, the contact protrusion 15B is in contact with the cam protrusion 3B. Since it is smaller (see FIG. 6F), the rotation operation rod 15 is rotated relative to the cover tray 7. For this reason, the bevel gear 13B moves while rotating around the bevel gear 15A, and the lock operating rod 13 rotates, so that the lock claw 13A is separated from the rack 9B and the engaged state is released (FIG. 6C). )reference).

  When the cover tray 7 is opened from the closed state, the rotation operation rod 15 cannot be rotated similarly to the cover tray 7 due to the elastic force of the engagement holding spring 17, and the rotation angle of the rotation operation rod 15 is Since the rotation angle is smaller than the rotation angle of the cover tray 7, the rotation operation rod 15 is rotated relative to the cover tray 7. For this reason, the bevel gear 13B moves while rotating around the bevel gear 15A, and the lock operation rod 13 rotates, so that the lock claw 13A moves to the rack 9B side and is in an engaged state.

4). As described above, in the present embodiment, when the extension tray 9 is displaced to the extension position side, the user manually performs the operation, so the paper size used by the user Accordingly, the user can displace the extension tray 9 to the extension position side by a necessary amount.

  Further, since the extension tray 9 displaced to the extension position side is displaced to the accommodation position in conjunction with the operation of closing the cover tray 7 by the user, the user separately operates to displace the extension tray 9 to the accommodation position side. There is no need, and user convenience is improved.

  In this embodiment, since the rack 9B is provided with irregularities, the extension tray 9 can be easily displaced when necessary even if the displacement of the extension tray 9 is normally regulated (locked) by the lock mechanism. Therefore, the extension tray 9 can be displaced to a position intended by the user.

Further, since the structure of the lock mechanism is simple (simple), the extension tray 9 can be easily displaced to the storage position side or the extension position side.
In the present embodiment, the lock operation bar 13 can be rotated about its own central axis, so that the engagement between the rack 9B and the lock claw 13A can be released.

  Moreover, in this embodiment, since the rotation operating rod 15 is rotated only when the restriction (locking) by the lock mechanism is released, it is possible to suppress an excessive increase in the operating force when the cover tray 7 is opened and closed. .

In the present embodiment, the sheet can be easily placed on the cover tray 7 with the rear end of the sheet aligned by making contact with the rear guide surface 9A so as to contact the rear end of the sheet.
That is, for example, the image forming apparatus described in Patent Document 1 can substantially align only one type of paper size, but in the present embodiment, the rear guide surface 9A can be at a position intended by the user. The rear guide surface can be effectively used for various sizes of paper.

5. Relationship between Invention Specific Items and Embodiments In this embodiment, the lock operation rod 13 corresponds to the lock member described in the claims, and the rotation operation rod 15 corresponds to the rotation operation member described in the claims. Equivalent to.

(Second Embodiment)
In the first embodiment, the interlocking mechanism is configured by the bevel gears 13B and 15A. However, in the present embodiment, as shown in FIG. 8, the protrusions 13D and 15D that abut against the lock operation rod 13 and the rotation operation rod 15 respectively. Etc. are provided to configure the interlocking mechanism. The description of the same configuration as that of the first embodiment is omitted.

1. Details of the interlocking mechanism In this embodiment, the cover tray 7 that swings with respect to the opening 3A is provided. The cover tray 7 is provided with an extension tray 9, a lock operation bar 13, and a rotation operation bar 15.

The cover tray 7 is assembled so as to be swingable with respect to the housing 3 by inserting a rotating shaft 50 provided in the housing 3 into a shaft hole (not shown) of the cover tray 7.
As shown in FIG. 9A, the rotating shaft 50 has a semicircular shape in cross section, and includes a flat surface portion 51 and a circumferential portion 52, and the right side of the casing 3 among the axial ends. The end on the surface side is formed integrally with the housing 3.

  The rotation operation rod 15 is a columnar rotation operation member extending in the axial direction of the rotation shaft 50. As shown in FIG. 9B, the end of the rotary operating rod 15 on the rotating shaft 50 side has a cut-out shape, and a notch 15C that makes contact with the flat portion 51 of the rotating shaft 50 on the surface is provided. (See FIG. 9C).

  Of the end portions in the axial direction of the rotation operation rod 15, the end portion on the opposite side to the rotation shaft 50 is oriented perpendicular to the axial direction of the rotation operation rod 15 and perpendicular to the installation surface of the image forming apparatus 1. A projecting portion 15D that projects in a direction inclined from the direction toward the extension tray 9 is provided.

  As shown in FIG. 8, the end of the lock operation rod 13 in the extending direction on the rotation shaft 50 side is a direction away from the rotation axis of the lock operation rod 13 and toward the right side, which is the projection 15D side. A projecting portion 13D projecting in the horizontal direction parallel to the installation surface of the forming apparatus 1 is provided.

  An engagement holding spring 17 is provided at the axial center of the lock operation rod 13. The engagement holding spring 17 applies a force to rotate the lock operation rod 13 in the direction in which the lock claw 13A rotates toward the rack 9B, and the protruding portion 13D is horizontal on the right side with the cover tray 7 open. (See FIGS. 10 (a) and 10 (d)).

  When the cover tray 7 is swung in the closing direction, the lock operating rod 13 is swung in conjunction with the cover tray 7. At this time, since the notch 15C of the rotating operation rod 15 is in contact with the flat surface portion 51, the rotating operation rod 15 remains fixed without rotating (see FIGS. 10B and 10E). .

  When the cover tray 7 is swung, the protrusion 13D of the lock operation rod 13 and the protrusion 15D of the rotation operation rod 15 come into contact with each other while the cover tray 7 is moved to the closed state. When the cover tray 7 is further swung after the projecting portions 13D and 15D come into contact with each other, the lock operating rod 13 swings while the projecting portion 13D is pushed by the projecting portion 15D. As a result, the protrusion 13D receives a rightward rotational force from the protrusion 15D around the axis of the lock operation bar 13, so that the lock operation bar 13 rotates right and the engagement state of the lock claw 13A with the rack 9B is released. (See FIG. 10 (c) and FIG. 10 (f)).

2. Features of the Image Forming Apparatus According to the Present Embodiment In this embodiment, the locking operation bar 13 and the rotation operation bar 15 are provided with protrusions 13D and 15D that are in contact with each other. A rotational force is applied to 13D, and the engagement of the lock claw 13A is released.

  Thereby, the extension tray 9 extended with respect to the cover tray 7 can be accommodated by the operation | movement which closes the cover tray 7, and it is not necessary for the user to operate | move the extension tray 9. FIG.

In addition, since only the protrusions 13D and 15D that abut against the lock operation rod 13 and the rotation operation rod 15 are provided as the interlocking mechanism, the interlocking mechanism can be configured with a simple configuration.
(Other embodiments)
In the above-described embodiment, the contact protrusion 15B is in contact with the cam protrusion 3B to suppress the rotation of the rotation operation rod 15, but in the present invention, the contact protrusion 15B is the device housing 3 or The rotation of the rotary operation rod 15 may be suppressed by contacting the installation surface of the image forming apparatus 1.

  In the above-described embodiment, the rack 9B is provided on the extension tray 9. However, the present invention is not limited to this, and the rack 9B is provided on the lock operation rod 13 (lock member) and locked to the extension tray 9. You may provide the nail | claw 13A.

  Moreover, in the above-mentioned embodiment, although what used bevel gears 13B and 15A as an interlocking mechanism was described, by providing the interlocking mechanism with gears having mutually different axial positions of the lock operation rod 13 and the rotation operation rod 15, The gear provided on the lock operation rod 13 may be moved while being rotated along the circumferential direction of the gear provided on the rotation operation rod, and the lock operation rod 13 itself may be lifted with respect to the cover tray 7.

Moreover, the lock mechanism and the lock release mechanism shown in the above-described embodiment are examples of these, and are not limited to the configurations shown in the above-described embodiment.
Further, the present invention is not limited to the above-described embodiment as long as it matches the gist of the invention described in the claims.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 3 ... Housing | casing, 3A ... Opening part, 3B ... Cam protrusion part, 5 ... Image forming part,
7 ... Cover tray, 7A ... Rotating shaft, 7B ... Placement surface, 9 ... Extension tray,
9A ... Rear guide surface, 9B ... Rack, 11 ... Coil spring, 13 ... Lock operation rod,
13A ... Lock claw, 13B ... Bevel gear, 15 ... Rotation operation rod, 15A ... Bevel gear,
15B: Contact protrusion, 17: Engagement holding spring.

Claims (10)

An image forming unit for forming an image on paper;
An apparatus housing provided with an opening for feeding paper to the image forming unit;
A cover tray that covers the opening and is rotatable around an axis that is horizontal with respect to the apparatus housing, and on which a sheet can be placed with the opening open;
An extension tray that is provided on the cover tray and is displaceable between a storage position and an extension position in a direction substantially parallel to the placement surface on which the paper is placed;
A first elastic member that constantly biases the extension tray toward the storage position;
A lock mechanism for restricting movement of the extension tray in the biasing direction by the elastic member in a plurality of stages;
An image forming apparatus comprising: a lock release mechanism that releases a restriction by the lock mechanism in conjunction with an operation of closing the cover tray. The locking mechanism is
A locking member that is substantially parallel to the direction of displacement of the extension tray and faces the extension tray;
A rack having a plurality of convex portions and concave portions along the displacement direction of the extension tray;
It consists of a lock claw that restricts the extension tray from moving to the storage position side by engaging with the convex portion or concave portion of the rack,
The extension tray is provided with either the rack or the locking claw,
The lock member is provided with either the rack or the lock claw,
The image forming apparatus according to claim 1, wherein the lock release mechanism operates one of the extension tray and the lock member in a direction to release the engagement between the rack and the lock claw. apparatus. The locking member is rotatable about its central axis extending parallel to the displacement direction;
The image forming apparatus according to claim 2, wherein the engagement between the rack and the lock claw is released by the rotation of the lock member. The unlock mechanism is
A rotation operation member extending in a direction parallel to the rotation axis of the cover tray and rotatable with respect to the cover tray;
A contact portion that is provided in the rotation operation member and contacts the device housing or an installation surface of the device housing when the cover tray is closed;
The image forming apparatus according to claim 3, further comprising: an interlocking mechanism that rotates the lock member by transmitting rotation of the cover tray in the closing direction to the lock member. The interlocking mechanism is
A first protrusion that is provided on the opposite side of the lock member at one end where the rack or the lock claw is provided and protrudes away from the central axis of the lock member;
A second projecting portion provided on the rotation operation member and projecting toward the first projecting portion;
5. The image forming apparatus according to claim 4, wherein the first protrusion and the second protrusion are brought into contact with each other by rotating the cover tray in a closing direction to rotate the lock member.   The image forming apparatus according to claim 5, further comprising: a second elastic member that is provided on the lock member and applies a force for rotating the lock member in a direction in which the rack and the lock claw are engaged. . The interlocking mechanism is
A first gear provided at the other end of the lock member on the opposite side of the rack or the one end provided with the lock pawl;
The image forming apparatus according to claim 4, wherein the image forming apparatus is a second gear that is provided in the rotation operation member and meshes with the first gear.   The image forming apparatus according to claim 6, wherein the first gear and the second gear are bevel gears.   A second elastic member is provided on at least one of the rotation operation member and the lock member, and applies a force for rotating the lock member in a direction in which the rack and the lock claw are engaged with each other. Item 9. The image forming apparatus according to Item 7 or 8.   10. A rear guide surface that protrudes in a direction that rises at a right angle from the placement surface and that can come into contact with the rear end in the paper feeding direction is provided on the extension tray. The image forming apparatus according to claim 1.

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