JP2009083947A - Paper feeder and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder capable of suppressing the height of loaded recording mediums to the loading height satisfying paper feeding and separating conditions by a regulation member provided on a side fence to regulate the height of loaded recording mediums even if recording mediums are forcedly pushed therein in loading; and to provide an image forming device provided with the paper feeder. <P>SOLUTION: This paper feeder has a paper feeding cassette B for setting recording medium P, a bottom plate 3 being movable in the paper feeding cassette B to load the recording mediums P, and the regulation member 2 for regulating the height of the loaded recording mediums P. The regulation member 2 releases the regulation for loading in the interlocking relationship with movement of the bottom plate 3 when the paper feeding cassette B is mounted on the image forming device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a paper feeding device having a paper feeding cassette on which various types of recording media can be set, and an image forming apparatus such as an electrophotographic, facsimile, and multi-function machine equipped with the paper feeding device.

In a paper feeding device having a paper feeding cassette capable of setting various types of recording media, when the recording media is overloaded, the mechanism in which the paper feeding pressure decreases as the number of recording media increases, The allowable load on the design may be exceeded, and there may be a problem that the bottom plate cannot be raised and paper cannot be fed.
In addition, in a mechanism in which the sheet feeding pressure increases as the number of recording media increases, the pressure increases excessively and the adhesion between the recording media increases, causing multiple multi-feeds and serious damage to the machine. May give.
In order to solve the various disadvantages described above, various solution techniques have been conventionally proposed for a paper feeding device mounted on an image forming apparatus (see, for example, Patent Documents 1 and 2).
In Patent Document 1, a technique for providing an electromagnetic solenoid for restricting the stacking height of transfer sheets by a lower limit position restricting means for restricting the lower limit position of the leading end pressing member of the transfer sheet and holding the lower limit position at a predetermined timing. Is disclosed.
According to this technology, it is possible to surely prevent the recording medium from being overloaded by the user, and even if the transfer paper is forcibly compressed and inserted, it is released during the paper feeding operation, so it is possible to prevent non-feeding due to overloading. Stable paper feeding performance can be obtained.

Further, in Patent Document 2, when the overload preventing means is in the first position, the overload preventing means is arranged in the height direction of the sheet material to be stacked while the end is in contact with the contact surface of the end regulating member. Is protruding from the abutment surface, a technique is disclosed that allows the user to easily recognize that the sheet material is excessively loaded, and to prevent a situation in which the sheet material is forcibly set to cause a feeding failure.
Further, according to this technique, when the overload preventing means is in the second position, the overload preventing means is retracted from the sheet material loading space side with respect to the contact surface of the end regulating member. When the sheets are stacked from the direction along the contact surface, there is no obstacle, and the sheet material can be stacked by a natural operation, so that the operability is improved. When the sheet materials are stacked substantially horizontally, the sheet materials can be set from above, so that operability is improved regardless of whether the user is right-handed or left-handed.
JP-A-6-171769 JP-A-11-165484

However, since the mechanism of Patent Document 1 uses a solenoid or a permanent magnet, the apparatus becomes complicated and the cost is high. Further, in the image forming apparatus disclosed in Patent Document 2, overloading forcefully pushed cannot be avoided because the overloading prevention mechanism cannot be released, so that unfeeding and double feeding cannot be avoided completely.
Accordingly, an object of the present invention is to provide a regulation member that regulates the stacking height of the recording medium provided on the side fence even if it is forcibly pushed in during the loading in consideration of the above-described situation. It is an object of the present invention to provide a sheet feeding device that satisfies a stacking height that satisfies the above and an image forming apparatus equipped with the sheet feeding device.

In order to solve the above-described problems, the invention described in claim 1 includes a paper feeding cassette for setting a recording medium, a movable bottom plate for loading the recording medium in the paper feeding cassette, In a paper feeding device having a regulation member for regulating the stacking height of the recording medium and a link member for connecting the regulation member and the bottom plate, the regulation member is attached to the image forming apparatus of the paper feeding cassette. In some cases, the sheet feeding device releases the stacking regulation in conjunction with the movement of the bottom plate transmitted by the link member.
According to a second aspect of the present invention, the restricting member is provided to protrude from the side fence that is provided in the paper feed cassette and presses a side edge of the recording medium to the recording medium stacking side, The paper feeding device according to claim 1, wherein a stacking height of the recording medium is regulated.
According to a third aspect of the present invention, there is provided the paper feed according to the first or second aspect, wherein the regulating member is provided on the side fence that presses a side edge of the recording medium and is movable together with the side fence. Features the device.
According to a fourth aspect of the present invention, when the paper feed cassette is set in the image forming apparatus, the regulating member is interlocked with the movement of the bottom plate rising and is not in contact with the recording medium. The paper feeding device according to any one of 1 to 3 is characterized.
According to a fifth aspect of the present invention, an image forming unit that records an image on a recording medium, a conveying unit that conveys the recording medium to the image forming unit, and the recording medium supplied to the conveying unit 5. The sheet feeding device according to claim 1, wherein the sheet feeding device includes: a sheet feeding unit configured to perform recording and a sheet feeding device including a sheet feeding cassette configured to set the recording medium. The image forming apparatus is equipped with the apparatus.

  According to the present invention, since the restriction member that restricts overloading of the recording medium cancels the load restriction during the paper feeding operation, stable paper feeding performance can be obtained.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of an image forming apparatus according to the present invention. Although not shown, the image forming apparatus A, which is an ink jet image forming apparatus, holds the carriage slidably in the main scanning direction with guide rods and guide rails which are guide members horizontally mounted on the left and right side plates. It is configured as follows.
In the carriage, for example, a recording head composed of four droplet ejection heads that eject ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk) is provided with a plurality of ink ejection ports. Are arranged in a direction crossing the main scanning direction, and the ink droplet ejection direction is directed downward.
On the other hand, the paper feeding device B feeds a recording medium (not shown) loaded on a paper stacking unit (pressure plate) 3 such as a paper feeding cassette toward an image forming unit (not shown). As shown in FIG. 1, a side fence 1 that presses the end surface in the conveyance direction of the recording medium is installed in the paper feeding device B to prevent skew.

The end of the recording medium in the conveyance direction hits the side fence 1 to prevent skew. A recording medium overloading restricting member (regulating member) 2 for restricting the number of recording media to be stacked is installed on the side fence 1.
A half-moon roller (paper feed roller) 4 for separating and feeding recording media (sheets) one by one from a recording medium stacking portion (bottom plate) 3 and a separation made of a material having a large friction coefficient facing the paper feeding roller 4. A pad 5 is provided, and the separation pad 5 is urged toward the paper feed roller 4 by appropriate means.
A transport belt for transporting the recording medium by electrostatic adsorption as a transport unit for transporting the recording medium fed from the paper feeding device B on the lower side of the recording head (not shown). 6 and a counter roller 8 for transporting the recording medium fed from the paper feeding device B via the guide 7 while being sandwiched between the transport belt 6.
The transport unit is further urged toward the transport belt 6 by a transport guide 9 for causing the recording medium to be sent substantially vertically upward to change the direction of the recording medium by approximately 90 ° and to follow the transport belt 6 and a pressing member 10. The tip pressurizing roller 11 is provided. In addition, a charging roller 12 that is a charging unit for charging the surface of the conveyance belt 6 is provided.

Here, the conveyance belt 6 is an endless belt, and is looped between the conveyance roller 13 and the tension roller 14 and rotates in the belt conveyance direction (sub-scanning direction) by rotating the conveyance roller 13. It is configured to do. A guide member 15 is disposed on the back side of the conveying belt 6 corresponding to the image forming area formed by the recording head.
Further, as a paper discharge unit for discharging the recording medium recorded by the recording head, a separation unit for separating the recording medium from the conveyance belt 6, a paper discharge roller 16, a paper discharge roller 17, and a discharge unit. And a paper discharge tray 18 for stocking the recording medium to be printed.
A double-sided paper feeding unit 19 is detachably mounted on the back. The double-sided paper feeding unit 19 takes in the recording medium returned by the reverse rotation of the conveying belt 6, reverses it, and feeds it again between the counter roller 8 and the conveying belt 6.
In the image forming apparatus A configured as described above, the recording media are separated and fed one by one from the paper feeding device B, and the recording media fed substantially vertically upward are guided by the guide 7 and are conveyed by the conveying belt 6. And the counter roller 8. Further, the front end is guided by the transport guide 9 and is pressed against the transport belt 6 by the front end pressure roller 11 to change the transport direction by approximately 90 °.
At this time, a positive voltage output and a negative output are alternately repeated from the high voltage power source to the charging roller 12 by a control circuit (not shown), that is, an alternating voltage is applied, and a charging voltage pattern in which the conveying belt 6 alternates, that is, In the sub-scanning direction, which is the circumferential direction, plus and minus are alternately charged in a band shape with a predetermined width.

When the recording medium is fed onto the conveying belt 6 that is alternately charged with plus and minus, the recording medium is attracted to the conveying belt 6 by electrostatic force, and the recording medium is moved by the circular movement of the conveying belt 6. It is conveyed in the sub-scanning direction.
Therefore, by driving the recording head according to the image signal while moving the carriage, ink droplets are ejected onto the recording medium that is stopped to record one line, and after the recording medium 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 recording medium has reached the recording area, the recording operation is terminated and the recording medium is discharged onto the discharge tray 18.
In the case of double-sided printing, when recording on the front surface (surface to be printed first) is completed, the recording medium to be recorded is fed into the double-sided paper feeding unit 19 by rotating the conveyor belt 6 in the reverse direction. The recording medium is reversed (with the back surface being the printing surface) and fed again between the counter roller 8 and the conveyor belt 6, and the timing control is performed, and on the conveyor bell 6 as described above. After transporting and recording on the back surface, the paper is discharged onto the paper discharge tray 18.

FIG. 2 is a plan view showing a paper feeding cassette of the paper feeding device. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2 showing the side fence and the overloading restricting member before the paper feed cassette is set in the image forming apparatus. FIG. 4 is a cross-sectional view showing the side fence and the overloading restricting member in the same part as in FIG. 3 when the paper feed cassette is set in the image forming apparatus and the bottom plate is raised by the link mechanism.
2 to 4, as described above, the side fence 1 that presses the end surface in the transport direction of the recording medium P is installed in the paper feeding cassette of the paper feeding device B in order to prevent skew. Yes. The side fence 1 is in contact with the end of the recording medium P in the transport direction to prevent skew.

A regulating member 2 that regulates the number of stacked recording media P is installed on the side fence 1. FIG. 3 shows a state of the side fence 1 and the regulating member 2 before the paper feed cassette is set in the image forming apparatus. When the recording medium P is loaded, the regulating member 2 regulates the recording medium P from above and cannot load more than the specified height.
In a paper feeding apparatus that informs the user of the upper limit of the loading capacity of the recording medium P by a display unit (for example, a decal is attached), there is no guarantee that the user can observe the loading capacity. In order to prevent overloading, it is possible to reliably prevent the recording medium P from being configured so that the recording medium P cannot be set, rather than notifying the user of the upper limit of the loading capacity.
Therefore, the regulating member 2 that regulates the stacking height of the recording media P provided on the side fence 1 can be set to a stacking height that satisfies the sheet feeding condition and the separation condition.
In this way, even if the recording medium P is forcibly pushed in at the time of loading, the regulating member 2 that regulates the loading height of the recording medium P provided on the side fence 1 should be less than or equal to the loading height that satisfies the sheet feeding conditions and the separation conditions. Can do.

The recording medium P to be loaded has various sizes, but it is not preferable for the user to perform a special operation for each size change. According to the present invention, as shown in FIGS. 3 and 4, the regulating member 2 is attached to the fulcrum 1 a on the side fence 1 and moves together with the side fence 1. Therefore, it can respond to various sizes with a simple operation.
As described above, in the present invention, by attaching the regulating member 2 to the side fence 1 and moving together with the side fence 1, various sizes can be handled with a simple operation.
If it is pushed in forcibly at the time of loading, non-feeding or multi-sheet feeding may occur due to stress or frictional force acting between the regulating member 2 and the recording medium P. The regulating member 2 that regulates the stacking height of the recording medium P provided on the side fence 1 becomes non-contact during the paper feeding operation.

In FIG. 4, the paper feed cassette (FIG. 2) of the paper feed device B is set in the image forming apparatus A (FIG. 1), is actuated by drive means not described in detail, and is composed of link portions 2 a and 1 b. The state of the side fence 1 and the regulating member 2 when the recording medium stacking portion (bottom plate) 3 is raised by the link mechanism (link member) is shown.
At this time, the regulating member 2 is pushed up by the recording medium stacking portion 3 around the fulcrum on the side fence 1, so that it is not in contact with the recording medium P. By releasing the regulating member 2 during the paper feeding operation, stable paper feeding performance can be obtained.

As shown in FIGS. 3 and 4, the regulating member 2 has a fulcrum 1a on the side fence 1 and rotates around the fulcrum 1a. When the paper feeding cassette of the paper feeding device B is set in the image forming apparatus A and receives the force that the recording medium stacking unit 3 ascends by the link mechanism, the regulating member 2 rises and is not in contact with the recording medium P. Become.
Since the ascending link mechanism of the regulating member 2 is configured in the sheet feeding cassette of the sheet feeding device B, when the ascending link mechanism of the regulating member 2 is broken, the entire sheet feeding cassette can be replaced.
In this way, the link mechanism that brings the regulating member 2 and the recording medium P into non-contact is accommodated inside the paper feed cassette, and can be completed only by replacing the paper feed cassette when it is broken.

1 is a schematic diagram showing an overall configuration of an embodiment of an image forming apparatus according to the present invention. It is a top view which shows the paper feed cassette of a paper feeder. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2 illustrating a state of the side fence and the regulating member before the paper feeding cassette is set in the image forming apparatus. FIG. 4 is a cross-sectional view showing the side fence and the regulating member in the same part as in FIG. 3 when a paper feed cassette is set in the image forming apparatus and a recording medium stacking portion is raised by a link mechanism.

Explanation of symbols

A image forming apparatus, B paper feeding device (paper feeding cassette), 1 side fence, 2 regulating member, 3 recording medium stacking section (bottom plate), 6 transport section (transport belt), 9 transport section (transport guide), 10 Conveying part (pressing member), 11 Conveying part (tip pressure roller)

Claims (5)

A paper feed cassette for setting a recording medium; a movable bottom plate for loading the recording medium in the paper feeding cassette; a regulating member for regulating a stacking height of the recording medium; the regulating member; In a paper feeding device having a link member that connects the bottom plate,
The sheet feeding device according to claim 1, wherein when the sheet feeding cassette is attached to the image forming apparatus, the regulation member releases the stacking regulation in conjunction with the movement of the bottom plate transmitted by the link member.   The restricting member is provided on the sheet feeding cassette and protrudes from the side fence that presses the side edge of the recording medium toward the recording medium stacking side, and regulates the stacking height of the recording medium. The sheet feeding device according to claim 1, wherein the sheet feeding device is provided.   The sheet feeding device according to claim 1, wherein the regulating member is provided on the side fence and is movable together with the side fence.   4. When the sheet feeding cassette is set in the image forming apparatus, the restricting member is interlocked with a movement of the bottom plate rising and is not in contact with the recording medium. The sheet feeder according to item 1.   An image forming unit that records an image on a recording medium, a conveying unit that conveys the recording medium to the image forming unit, a paper feeding unit that supplies the recording medium to the conveying unit, and the recording medium An image forming apparatus having a sheet feeding device including a sheet feeding cassette to be set, wherein the sheet feeding device according to any one of claims 1 to 4 is mounted as the sheet feeding device. apparatus.

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