JP2012046302A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of preventing an extended dust cover from being returned to an original position, with a simple and low-cost configuration.SOLUTION: The image forming apparatus includes a paper feed tray 20 which stores sheets to be supplied to the apparatus body, and can be attached/detached to/from the apparatus body, and in the image forming apparatus, wherein the paper feed tray 20 is configured to change the size thereof between a standard form and an extension form so as to cope with the change of the size of a recording medium to be stored therein. The image forming apparatus also includes: the dust cover 80 loaded to the apparatus body so that it can directly or indirectly slide; stopper members 100, each of which is made movable between a blocking position and a permission position to block and permit the movement of the dust cover 80. The stopper member 100 is usually held in the permission position, and when the paper feed tray 20 is changed from the standard state to the extension state, and also, when the dust cover 80 is moved to an extension position, the stopper member 100 is moved from the permission position to the blocking position.

Description

  The present invention relates to an image forming apparatus having a paper feed tray that can be expanded and contracted between a standard form and an extended form so that the size of a recording medium to be accommodated can be changed.

  2. Description of the Related Art In an image forming apparatus used as various image forming apparatuses such as a printer, a facsimile machine, a copying apparatus, and a plotter, it is well known to supply a recording medium such as paper from a paper feed tray into the apparatus. In this type of image forming apparatus, the paper size that can be accommodated by extending a part of the tray is expanded as described above. For example, a part of the tray that accommodates A4 size paper is extended to accommodate A3 size paper. It is also known to provide a paper feeding device that can be changed to a paper feeding tray that can be changed.

  For example, in an ink jet recording apparatus having a paper feed tray and a paper discharge tray for stocking paper on which an image is recorded, if the paper feed tray is extended to a size larger than A4 size, The split paper feed tray protrudes from the apparatus main body, and an opening is formed between the paper feed tray and the paper discharge tray above it. If the opening is left as it is, there is a risk that dust or the like may enter the paper feed tray from the opening, or an erroneous operation may be performed in which additional paper is replenished from the opening despite printing. It was. In view of this, there has been proposed a recording apparatus provided with a cover for covering the opening (hereinafter referred to as a dust cover) for the purpose of preventing dust intrusion and paper replenishment during printing.

  There are two types of this type of recording device: a dust cover that can be removed and a member that is independent of the paper feed tray and paper discharge tray, and a dust cover that slides to close the opening. The slide type is preferred.

  This sliding dust cover can be freely expanded and contracted even during printing, so if you return it to its original position, the dust cover will not function and dust such as dust will enter from the opening. There is a risk that an erroneous operation is performed such that additional paper is replenished from the opening despite printing.

  Patent Document 1 discloses a recording apparatus that can eliminate such a problem. In the apparatus of this patent document 1, the dust cover can be automatically extended by the extension operation of the paper feed tray, and the extension of the paper feed tray and the extension of the dust cover are interlocked. It can be prevented from returning.

  However, in the apparatus of Patent Document 1, it is necessary to raise the lifting rack part having a length of at least about the extension by pulling out the paper feed tray extension part from the paper feed tray base part. There was also a problem that would increase.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus capable of solving the above-described conventional problems and prohibiting an extended dust cover from being returned to its original position with a simple and inexpensive configuration.

  In order to achieve the above object, the present invention accommodates a recording medium to be supplied to an image forming apparatus main body, and has a paper feed tray that can be attached to and detached from the image forming apparatus main body. In an image forming apparatus configured to be changeable between a standard form and an extended form so that the size can be changed, the image forming apparatus is slidably mounted directly or indirectly on the main body of the image forming apparatus, and the paper feed tray in the extended form A cover member that can be moved to an extended position that covers an upper portion of the cover, and a stopper member that can be moved between a blocking position that prevents the movement of the cover member and an allowable position that allows the movement of the cover member. The member is normally held in an allowable position, and when the paper feed tray is changed from the standard form to the extended form, and the cover member is moved to the extended position, the member is moved from the allowable position to the blocking position. We propose an image forming apparatus characterized by.

  According to the present invention, it is advantageous that the stopper member is provided on the tray body of the paper feed tray, and the stopper member moves from the allowable position to the blocking position by the pressing force of the elastic body or its own weight.

Further, according to the present invention, it is advantageous that the stopper member is provided on a paper discharge tray that covers the paper feed tray, and the stopper member moves by its own weight from the allowable position to the blocking position.
Furthermore, in the present invention, it is advantageous that the stopper member is provided on a side plate adjacent to the sheet feeding tray of the image forming apparatus main body, and the stopper member is moved from the allowable position to the blocking position by the pressing force of the elastic body. It is.

  According to the present invention, the paper feed tray is changed from the standard form to the extended form, and the cover member is moved to the extended position, and the cover member is extended to the extended position that covers the upper part of the paper feed tray in the extended form. As a result, the stopper member that prevents the movement of the cover member moves from the allowable position that allows the movement to the blocking position that prohibits the movement, so that it is possible to reliably inhibit returning the extended cover member to the original position. .

FIG. 3 is a perspective explanatory view seen from the front side of the image forming apparatus according to the present invention. FIG. 2 is a configuration diagram illustrating an outline of a mechanism unit of the recording apparatus. It is principal part plane explanatory drawing of the mechanism part. It is a perspective view showing a paper feed tray to which the present invention is applied. 1A and 1B show an embodiment of the present invention, in which FIG. 3A is an explanatory diagram viewed from a side direction in a state in which a dust cover is pulled out, and FIG. It is explanatory drawing seen from the front direction which shows the modification of the stopper member means of FIG. It is explanatory drawing seen from the side surface direction of embodiment shown in FIG. It is explanatory drawing seen from the side surface direction which shows another embodiment of this invention. 4A and 4B show still another embodiment of the present invention, in which FIG. 4A is a diagram illustrating a dust cover when the paper feed tray is moved, and FIG. 5B is a diagram illustrating a dust cover when the paper feed tray is mounted. It is explanatory drawing seen from the side surface direction which shows the form at the time of a movement. It is explanatory drawing seen from the front direction of embodiment shown in FIG. It is a figure explaining the effect of embodiment shown in FIG. It is explanatory drawing seen from the side surface direction which shows another embodiment of this invention. It is explanatory drawing seen from the front direction of embodiment shown in FIG. It is explanatory drawing seen from the plane direction of embodiment shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is an explanatory perspective view of an ink jet recording apparatus as an image forming apparatus according to the present invention as viewed from the front side.

  The ink jet recording apparatus shown here includes an apparatus main body 1, a paper supply apparatus 2 including a paper supply tray 20 for loading paper that is a recording medium mounted on the apparatus main body 1, and paper on which image recording has been completed. And a paper discharge tray 3 for stocking. Further, the front surface 4 of the apparatus main body 1 has a cartridge loading portion 6 that protrudes from the front surface 4 to the front side at one end side thereof and is lower than the upper surface 5. An operation unit 7 such as a vessel is arranged. The cartridge loading unit 6 is detachably mounted with main ink tanks 10Y, cyan 10C, magenta 10M, and black 10K of yellow (Y), cyan (C), magenta (M), and black (K). Yes.

  In the apparatus main body 1, as shown in FIGS. 2 and 3, the carriage 13 is slid in the main scanning direction by a guide rod 11 and a stay 12 which are guide members horizontally mounted on left and right side plates (not shown). It is held movably and moved and scanned in the direction of the arrow in FIG. 3 by a main scanning motor (not shown).

  The carriage 13 has two head recording heads 14, two heads and four tank heads each having four sub tanks 15. The four tanks have yellow (Y), cyan (C), magenta (M), black ( Bk) recording ink of each color is stored, and the recording head 14 is arranged with a plurality of ink ejection openings arranged in a direction crossing the main scanning direction, and the ink droplet ejection direction is directed downward.

  The inkjet recording head constituting the recording head 14 includes a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by liquid film boiling using an electrothermal transducer such as a heating resistor, and a metal phase caused by a temperature change. A shape memory alloy actuator using a change, an electrostatic actuator using an electrostatic force, or the like provided as energy generating means for discharging recording ink can be used.

  In addition, the carriage 13 is equipped with a sub tank 15 for each color for supplying ink of each color to the recording head 14. The sub tank 15 is supplied with the recording ink from the ink cartridge 10 loaded in the ink cartridge loading section 6 via the recording ink supply tube and is replenished.

  On the other hand, the sheet feeding device 2 has a sheet feeding tray 20, and further opposes the half-moon roller (sheet feeding roller 71) that separates and feeds the sheets P stacked on the sheet feeding tray 20 one by one, and the sheet feeding roller 71. In addition, a separation pad 72 made of a material having a large friction coefficient is provided, and the separation pad 72 is urged toward the paper feed roller 71.

  As a transport unit for transporting the paper P fed from the paper feed device 2 below the recording head 14, a transport belt 31 for transporting the paper P by electrostatic adsorption and the paper feed device 2 The counter roller 32 for transporting the paper P sent via the guide 73 while sandwiching it between the transport belt 31 and the paper P sent substantially vertically upward are changed by about 90 ° and copied onto the transport belt 31. A charging guide 36 and a tip pressure roller 35 urged toward the conveying belt 31 by a pressing member 34, and a charging roller 36 as a charging means for charging the surface of the conveying belt 31. Is provided.

  The conveyance belt 31 is an endless belt, is stretched between the conveyance roller 37 and the tension roller 38, and can circulate in the belt conveyance direction. A guide member 77 is disposed on the back side of the conveyance belt 31 so as to correspond to a printing area by the recording head 14. As a paper discharge unit for discharging the paper P recorded by the recording head 14, a separation claw 51 for separating the paper P from the transport belt 31, a paper discharge roller 52, and a paper discharge roller 53 are provided. The paper discharge tray 3 is disposed below the paper discharge roller 52.

  A double-sided paper feeding unit 61 is detachably attached to the back surface of the apparatus main body 1. The double-sided paper feeding unit 61 takes in the paper P returned by the reverse rotation of the transport belt 31, reverses it, and feeds it again between the counter roller 32 and the transport belt 31. A manual paper feed unit 62 is provided on the upper surface of the duplex paper feed unit 61.

  In this ink jet recording apparatus, the paper P is separated and fed one by one from the paper feeding device 2, and the paper P fed substantially vertically upward is guided by the guide 28, and is fed between the transport belt 31 and the counter roller 32. It is sandwiched and conveyed. Further, the front end is guided by the transport guide 33 and pressed against the transport belt 31 by the front end pressure roller 35, and the transport direction is changed by approximately 90 °.

  At this time, the conveyance belt 37 is charged by the charging roller 36, and the paper P is electrostatically attracted to the conveyance belt 31 and conveyed. Therefore, by driving the recording head 14 according to the image signal while moving the carriage 13, ink droplets are ejected onto the stopped paper P to record one line, and after the paper P is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the paper P has reached the recording area, the recording operation is finished and the paper P is discharged onto the paper discharge tray 3.

  Then, when it is detected that the remaining amount of recording ink in the sub tank 15 has decreased, a required amount of recording ink is supplied from the ink cartridge 10 to the sub tank 15. Here, an example is described in which the present invention is applied to a serial (shuttle type) ink jet recording apparatus that is scanned by a carriage, but the present invention can be similarly applied to a line type ink jet recording apparatus having a line type head.

  The paper feeding tray 20 of the paper feeding device 2 can be adjusted according to the paper size on which side fences and end fences (not shown) provided therein are placed so that a plurality of different sizes of paper can be stacked. . This adjustment operation can be performed by pulling out the paper feed tray 20 from the apparatus main body 1. Furthermore, the paper feed tray 20 of the present embodiment includes an expansion mechanism that can place a paper having a size larger than a predetermined size. That is, as shown in FIG. 4, the paper feed tray 20 includes a tray main body 21 and an extension tray 22 that can be pulled out from the tray main body 21, and enables loading of paper having a size larger than a predetermined size. Has a stretch function. The operation of extending the paper feed tray 20 is performed after the paper feed tray 20 is pulled out from the apparatus main body 1 in the same manner as the adjustment operation.

  By the way, since the upper surface of the paper feed tray 20 is covered with the paper discharge tray 3, the entry of dust and the like into the tray is suppressed, and the addition of paper during printing is prevented. However, the extended paper feed tray 20 cannot be covered with the paper discharge tray 3 as shown in FIG. 4, and an opening is formed. Therefore, a dust cover 80 is provided as a cover member that slides out to the paper discharge tray 3 and extends.

  However, if the dust cover 80 can be returned to its original position from the extended state, there is a problem that it is not possible to prevent the above-described intrusion of dust or the like and the addition of paper during printing. explained.

  Therefore, in the present invention, there is provided a stopper member means that the dust cover 80 that is pulled out cannot be returned to the original storage position unless the paper feed tray 20 is removed from the apparatus main body 1, and will be described in detail.

  5A, a stopper member 100 as a stopper member means is provided on the tray main body 21 of the paper feed tray 20 so as to be movable up and down, and an elastic action that is pushed upward by a pressing spring 101 is urged. When the dust cover 80 is housed without the paper feed tray 20 being extended, the stopper member 100 has the head of the stopper member 100 dust-free by the elastic force of the pressing spring 101, as is apparent from FIG. It is located at a standby position in contact with the bottom surface of the cover 80. When the paper feed tray 20 is expanded and the dust cover 80 is pulled out to the left in the drawing and reaches a predetermined extended position, the dust cover 80 is separated from the stopper member 100, and the stopper member 100 is moved upward by the pressing spring 101. It is moved to the stop position pushed up. If this stopper member 100 is moved to the stop position, even if it tries to return the dust cover 80 to the original position, it will hit the stopper member 100 and no further return will be possible.

  Thus, it is possible to prevent the dust cover 80 covering the extended portion from being returned to the original position, thereby preventing entry of dust or the like due to movement of the cover and addition of paper during printing. The stopper members 100 are provided on both sides of the paper feed tray 20 to stop the dust cover 80 with good balance.

  FIG. 6 shows a modified example of the stopper member means of FIG. 5, guide portions 104 for restricting the stopper member 100 are provided on both side surface portions 103 to which the sheet feeding tray 20 of the apparatus main body 1 is mounted, and the other stopper member 100 A regulating shaft 102 is provided on the surface facing the side surface portion. The restriction shaft 102 is brought into contact with the guide portion 104 by a pushing force by the pressing spring 101.

  FIG. 7 shows the locus of the stopper member 100 when the paper discharge tray 3, the dust cover 80, and the extension tray 22 shown in FIG. 6 are pulled out. In this case, the display of the paper feed tray 20 is omitted, and the stopper member 100 and the side surface portion are shown. 103 guide portions 104 are displayed. In addition, although the structure shown here is the left side surface side of FIG. 6, this structure is provided symmetrically.

  In FIG. 7, the stopper member 100 supported by the paper feed tray 20 is a guide portion provided on the side surface portion 103 of the apparatus main body 1 when the paper feed tray is moved to the right in FIG. It is raised from the standby position to the stop position via the regulating shaft 102 along the guide shape 104. The stopper member 100 is raised when the dust cover 80 is pulled out. The guide portion 104 may be formed integrally with the side surface portion 103 or may be fixed to the side surface portion 103 as a separate part.

  Next, the reverse operation, that is, when the paper feed tray 20 mounted on the apparatus main body 1 is pulled leftward in FIG. 7, the stopper member 100 is lowered along the guide portion 104. Accordingly, when the stopper member 100 is raised, that is, when the paper feed tray 20 is mounted on the apparatus main body 1, the dust cover 80 cannot be stored. When the paper feed tray 20 is pulled out, that is, when the stopper member 100 is lowered, The stopper member 100 returns from the stop position to the standby position, the lock is released, and the dust cover 80 can be freely stored.

  FIG. 8 shows a modified example of the stopper means of FIG. 7. In this example, guide grooves 106 for restricting the upper and lower surfaces of the restriction shaft 102 are formed as guide portions of the side surface portion 103, and accompanying the attachment / detachment operation of the paper feed tray 20 The stopper member 100 is guided and moved along the upper and lower edges of the guide groove 106. That is, when the paper feed tray 20 is moved to the right, the stopper member 100 is raised by being regulated by the shape of the lower edge of the guide groove 106, and when the paper feed tray 20 is moved to the left, the guide groove 106 is The stopper member 100 can be lowered by being regulated by the shape of the edge. As a result, even if the stopper member 100 is not supported by an elastic body such as a spring, the stopper member 100 can be moved between the stop position and the standby position, and the number of parts can be reduced.

  FIG. 9 is an explanatory view showing another embodiment of the present invention. The stopper member 200 of this embodiment is supported by the paper discharge tray 3. The shape of the stopper member 200 will be described. As shown in FIGS. 9 and 10, the left and right side plates of the paper feed tray 20 are provided on the left and right sides, and arm portions 201 formed in a U-shape are provided on the outside thereof. Further, a thin plate-like collar portion 202 is provided on the upper surface thereof. The stopper member 200 is mounted in a holding recess 3a formed on the paper discharge tray 3 so as to be vertically movable. Normally, the stopper member 200 of the holding recess 3a placed on the dust cover 80 as shown in FIG. Although it is located at the upper part, when it is lowered, it is configured such that the collar 202 moves to a position where it comes into contact with the holding edge 3b of the holding recess 3a as shown in FIG. 9B. On the other hand, the tray body 21 of the paper feed tray 20 is formed with a U-shaped receiving portion 21 a that engages with the U-shaped arm portion 201 at the position where the stopper member 200 is provided. In addition, the taper shape 203 which promotes the smooth raising of the stopper member 200 when the paper feed tray 20 is taken out on the mutually opposing surfaces of the stopper member 200 and the tip of the dust cover 80 and when the dust cover 80 is returned. 80a is formed.

  In the image forming apparatus configured as described above, when the paper feed tray 20 is taken out and the dust cover 80 is pulled out, the stopper member 200 is lowered to the position shown in FIG. Then, when the taken-out paper feed tray 20 is extended and then reattached to the apparatus main body 1, the receiving portion 21a of the tray main body 21 is engaged with the arm portion 201 of the stopper member 200 that is lowered. Even when trying to return the dust cover 80 to the original position in this state, the tip in the return direction hits the stopper member 200. At this time, even if the stopper member 200 moves upward in the taper shapes 203 and 80a, Since the arm portion 201 is engaged with the receiving portion 20a, the stopper member 200 does not rise, and the operation of returning the dust cover 80 can be reliably prevented.

  Thus, the image forming apparatus according to the present embodiment can prevent the dust cover 80 covering the extended portion from being returned to the original position without using the elastic member held by the stopper member 200. Therefore, the cover is moved during the extension. Therefore, it is possible to reliably prevent entry of dust and the like and addition of paper during printing. Furthermore, in this embodiment, the stopper member 200 provided on the dust cover 80 engages with the paper feed tray 20, so that the paper discharge tray 3 and the dust cover 80 as shown in FIG. Can also be prevented from rotating.

  FIG. 12 is an explanatory view showing still another embodiment of the present invention, and the stopper member 300 of this embodiment is supported on the side plate 1 a of the apparatus main body 1. The shape of the stopper member 300 will be described. As shown in FIGS. 12 and 13, a protruding portion 302 is formed at one end of a shaft portion 301 whose axis is horizontal, and a U-shaped engaging recess 303 is formed at the other end. The projecting portion 302 side is loosely fitted into holding recesses 1b formed on both side plates 1a of the apparatus main body 1 so that the axis of the shaft portion 301 is substantially horizontal. The stopper member 300 loosely fitted in the holding recess 1b is always urged by a moving force that protrudes inward by a spring 304 as an elastic means, and normally comes into contact with the side edge of the dust cover 80 to enter the holding recess 1b. In the state where the dust cover 80 is removed and protrudes inward, the overhanging portion 302 is configured to move to a position where it abuts on the holding edge 1c of the holding recess 1b as shown in FIG. Yes. On the other hand, the tray main body 21 of the paper feed tray 20 is formed with an engaging convex portion 21 b that engages with the U-shaped engaging concave portion 303 at the position where the stopper member 300 is provided. As shown in FIG. 14, the stopper member 300 and the tip of the dust cover 80 are opposed to the spring 304 when the paper feed tray 20 is taken out and when the dust cover 80 is returned. Tapered shapes 305 and 80b are formed to be returned to the holding recess 1b against the above action.

  In the image forming apparatus configured as described above, when the paper feed tray 20 is taken out and the dust cover 80 is pulled out, the stopper member 300 is moved to the inner position shown in FIG. Moving. Then, after the sheet feeding tray 20 taken out is extended and then reattached to the apparatus main body 1, the engaging convex portion 21 b of the tray is engaged with the engaging concave portion 303 of the stopper member 300. Even if the dust cover 80 is returned to the original position in this state, the tip in the return direction hits the stopper member 300. At this time, even if the stopper member 200 tries to return to the holding recess 1b with the taper shapes 305 and 80b, it is engaged. Since the convex portion 21b and the engaging concave portion 303 are engaged, the operation of returning the dust cover 80 is prevented.

  The image forming apparatus according to the present invention is not limited to a printer having a single function configuration, and may be an image forming apparatus having a composite function such as a printer, a facsimile machine, a copying machine, and the like. A paper tray is also applied to these image forming apparatuses.

DESCRIPTION OF SYMBOLS 1 Apparatus main body 2 Paper feeder 3 Paper discharge tray 20 Paper feed tray 21 Tray main body 22 Extension tray 80 Dust cover 100,200,300 Stopper member

JP 2008-254848 A

Claims (4)

A standard form and an extended form have a recording medium supplied to the main body of the image forming apparatus, a detachable paper feed tray in the main body of the image forming apparatus, and the size of the recording medium accommodated in the paper feeding tray can be changed. In the image forming apparatus configured to be changeable to
A cover member that is slidably mounted directly or indirectly on the image forming apparatus main body, and is movable to an extended position that covers an upper portion of the paper feed tray in the extended form;
A stopper member movable between a blocking position for blocking the movement of the cover member and an allowable position for allowing the movement of the cover member;
The stopper member is normally held at an allowable position, and when the paper feed tray is changed from the standard form to the extended form, and the cover member is moved to the extended position, the stopper member is moved from the allowable position to the blocking position. An image forming apparatus.   The image forming apparatus according to claim 1, wherein the stopper member is provided on a tray main body of the paper feed tray, and the stopper member moves from an allowable position to a blocking position by a pressing force of an elastic body or its own weight. An image forming apparatus.   2. The image forming apparatus according to claim 1, wherein the stopper member is provided on a paper discharge tray that covers the paper feed tray, and the stopper member moves by its own weight from the allowable position to the blocking position. Forming equipment.   2. The image forming apparatus according to claim 1, wherein the stopper member is provided on a side plate adjacent to the sheet feeding tray of the image forming apparatus main body, and the stopper member presses the elastic body from the allowable position to the blocking position. An image forming apparatus which is moved by

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