JP2001310828A - Paper feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeding device enabling an user to easily and certainly change pressure for paper feeding, and easily stabilizing paper feeding performance. SOLUTION: This paper feeding device 12 is provided with a driving means by a motor, and a rising detecting sensor for a paper feeding pressure setting lever to have a mechanism capable of changing the paper feeding pressure. In the paper feeding device 12, an adjusting means for the paper feeding pressure is provided on a tray 110. Therefore, even if a kind of paper used for an image forming device is different, the paper feeding pressure is adjusted according to the paper, thereby preventing a jam in a paper carrying passage in the image forming device or a mistake in feeding from the paper feeding tray 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder used in an image forming apparatus such as a copying machine, a facsimile, a printer, and a multifunction machine. More specifically, the present invention relates to a paper feeder used in an image forming apparatus. The present invention relates to a paper feeding device for adjusting a paper feeding pressure.

[0002]

2. Description of the Related Art In recent years, in apparatuses such as copying machines and laser printers, there is an increasing need for printing on special-purpose paper such as postcards and OHPs. On the other hand, in order to meet such demands, stabilizing the performance of the sheet feeding device is an essential issue. In a paper feed device of a friction pad separation type or the like, the influence of the paper feed pressure on the paper feed performance is large, and the stabilization of the paper feed pressure can be said to be the stabilization of the paper feed performance. However, with respect to the use for special paper as described above, by making the paper feed pressure variable, it is possible to cope with a problem such as non-feed by any chance.

In order to make the paper feeding pressure variable, for example, in Japanese Patent Application Laid-Open No. Hei 6-127710, a pressure spring for lifting up a bottom plate supporting paper and a vertical position of a lower end of the pressure spring are described. There has been proposed a paper feed cassette provided with an adjusting means for adjusting the distance. Further, Japanese Unexamined Patent Publication No.
Japanese Patent No. 58472 discloses an intermediate plate on which sheets are stacked, and pressurizing means for pressing the sheet against a rotary feeder. The pressurizing means includes an intermediate plate pressing arm and an intermediate plate attached to the rotary feeder. A sheet feeding apparatus and an image forming apparatus having a biasing spring and an elastic force changing unit for changing an elastic force of the spring have been proposed. Further, in Japanese Patent Application Laid-Open No. Hei 7-237760, a pressing force changing means for changing the pressing force of the sheet pressing means is provided by a sheet feeding means for adjusting the pressing force by a control means based on the detection results of the sheet size detecting means and the sheet residual detecting means. An apparatus and an image forming apparatus including the same have been proposed. Japanese Patent Application Laid-Open No. 8-73056 discloses a paper feed pressure correcting means for automatically keeping a paper feed pressure by a pressurizing means for pressing a sheet to a rotary feeder constant according to the remaining amount or size of the stacked sheets. And an image forming apparatus having the same.

[0004]

However, the above-mentioned paper cassette and the like have the following problems. The paper feed cassette disclosed in Japanese Patent Application Laid-Open No. HEI 6-127710 has a paper feed pressure adjusting means in a tray, but the adjustment is not easy, and there is a problem that a special technician such as a service person can perform the adjustment. Further, the sheet feeding apparatus and the image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 5-58472 have a paper feed pressure adjusting means, but the adjustment is not easy, and there is a problem that only a special technician such as a service person can perform the adjustment. . Further, the paper feeder disclosed in JP-A-7-237760 and the image forming apparatus provided with the same, and the paper feeder and the image forming apparatus described in JP-A-8-73056, have a paper feed pressure adjusting means on a tray or a main body. However, since the user can arbitrarily change the operation, there is a problem in that the cost is increased due to the addition of the hardware SW or the operability is deteriorated due to the addition of the software SW, and it is difficult for the user to easily operate.

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to make it possible to easily change the paper feeding pressure at the user level and to stabilize the paper feeding performance. An object of the present invention is to provide a sheet feeding device that can be easily manufactured. It is still another object of the present invention to provide a sheet feeding device that allows the user to easily determine the current sheet feeding pressure state at a glance. It is another object of the present invention to provide a paper feeder that allows a user to easily determine the current paper feed pressure state at a glance, and that enables multi-stage pressure adjustment by using a dial type. . Also,
Another object of the present invention is to provide a sheet feeding device that can be finely adjusted by an operation unit or the like. Another object of the present invention is to provide a sheet feeding device that improves the impact resistance when the tray is pulled out. Another object of the present invention is to provide a sheet feeding device that improves operation stability. Another object of the present invention is to provide a sheet feeding device capable of detecting a current pressure set value. Another object of the present invention is to provide a sheet feeding device capable of notifying a user of a current pressure set value.

[0006]

According to a first aspect of the present invention, there is provided a driving apparatus comprising: a motor driving means; and a sensor for detecting a rising of a sheet feeding pressure setting lever. A paper feeder having a mechanism that can be changed, wherein the tray has a paper feed pressure adjusting unit. The invention described in claim 2 is:
The feeding device according to any one of the above, wherein the adjusting means adjusts the feeding pressure by a slide lever. The invention according to claim 3 is the paper feeder according to claim 1, wherein the adjusting means adjusts the paper feed pressure by a dial-type lever. Claim 4
The invention described in (1) is the paper feeder according to any one of claims 1 to 3, wherein the motor is stopped at the sensor position and then reversely rotated. According to a fifth aspect of the present invention, there is provided the sheet feeding apparatus according to any one of the first to fifth aspects, wherein a buffer member is added to the sheet feeding pressure setting lever. The invention according to claim 6 is the paper feeder according to any one of claims 1 to 5,
A sheet feeding device through which the harness of the upper limit detection sensor passes near the fulcrum of the sheet feeding pressure setting lever. The invention according to claim 7 is
7. The sheet feeding device according to claim 1, wherein the sheet feeding pressure set value can be detected by the main body.
The invention according to claim 8 is the paper feeder according to claim 7, wherein the operation unit notifies the paper feed pressure.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus using a sheet feeding device according to an embodiment of the present invention. Here, a specific example of a digital multifunction peripheral having two-stage paper feeding is shown. FIG. 2 is a schematic diagram illustrating a configuration of a sheet feeding device according to an embodiment of the present invention.
The image forming apparatus main body includes at least a bottom plate 134, a paper feed roller 103, a separation pad (friction pad) 104,
A paper supply unit 12 including a paper supply tray 110 and the like, a registration roller 6, a process unit including a photoconductor 4, a developing unit 9, a charging unit 11, a cleaning unit 10, and the like, and a fixing unit including a fixing roller and a pressure roller. The unit 3 includes a paper discharge roller pair 2 and an optical writing unit 8. Here, the operation of image formation will be described. The photosensitive member 4 having the photosensitive layer is rotated, and the surface thereof is uniformly charged by applying a voltage to a charging roller serving as the charging unit 10. Next, the optical writing unit 8
Irradiates a laser beam corresponding to image information from the outside onto the photoconductor 4 through an exposure opening to form a latent image. Then, the developing roller incorporating the fixed magnet is rotated, and a developer layer provided with a triboelectric charge by a developer regulating member (not shown) is formed on the surface of the developing roller, and is formed by the photoconductor and the developing roller. To the development area to be developed. Next, the developer is transferred to the photoreceptor 4 in accordance with the latent image and is visualized to form an unfixed toner image. Further, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 5 to transfer the toner image formed on the photoconductor 4 to a sheet. Thereafter, the cleaning unit 11 scrapes off and stores the developer remaining on the photoconductor 4 with an elastic cleaning blade provided in contact with the photoconductor 4. The paper in the paper feed tray 110 is transported by the paper feed roller 103 and the registration roller 6, and the toner image formed on the photoconductor 4 is transferred to the paper by applying a voltage to the transfer roller 5.

Here, the operation of paper transport will be described in detail with reference to the paper feeder of FIG. A paper feed tray 110110 for storing sheets cut to a predetermined size such as A4 and B5, a paper feed roller 103 for sequentially taking out the sheets one by one from the paper feed tray 110, and a relay conveyance drive roller for conveying the sheets And a feed roller 1 supported by a rotation fulcrum on the upstream side in the sheet conveying direction.
The bottom plate 134 is urged toward the 03 side, and the friction pad 104 is attached to the upper surface of the bottom plate 134 and pressed against the paper feed roller 103. This friction pad 104 is located on the downstream side in the transport direction of the paper transported by the paper feed roller 103 and
03 is elastically contacted with the outer peripheral surface. The paper is taken out of the paper feed tray 110 by the paper feed roller 103 and sent to a pressure contact portion between the paper feed roller 103 and the friction pad 104. The friction pad 104 uses the difference in the frictional force between the paper and the paper feed roller 103, between the paper and the paper, and between the paper and the friction pad 104 to remove the paper by one.
Separately feed each sheet. At this time, the sheet may be separated by any method such as a separation claw method and a friction roller method. The separated paper is placed in the paper feed tray 1
The paper is conveyed from 10 by the paper feed roller 103, reaches the relay driving unit, and is conveyed to the driving unit by the relay conveyance driving roller and the relay conveyance driven roller. Here, the timing for transferring the toner image is synchronized, and the toner image is conveyed to the transfer roller 5 by the registration driving roller and the registration driven roller. The same applies to manual paper feeding for paper conveyance. Thereafter, the sheet on which the toner image has been transferred is transported to the fixing unit 3. The fixing unit 3 includes a pressure roller and a fixing roller having a built-in heater. Then, heat and pressure are applied to the passing paper to fix the transferred toner image. This paper is transported by the discharge roller 2 and
The sheet is discharged to a sheet discharge section outside the image forming apparatus through the discharge port.

FIG. 3 is an external view when paper is fed to the paper feeding device according to the first, second and fourth aspects of the present invention. FIG. 4 is a schematic diagram showing the configuration of the sheet feeding device according to the first, second, and fourth aspects. As described above, the paper on the paper feed tray 110 is fed. Here, when the paper feed tray 110 is set, the paper is connected to the lifting lever 106 for raising the bottom plate 134 of the paper feed tray 110. The rising shaft 129 and the coupling 128 mesh with each other. When the detection sensor 102 detects that the paper feed tray 110 has been set, the paper feed pressure setting motor 122 rotates in the direction of arrow A. As a result, the feed pressure setting spring 123 is extended by engaging with the lever 121. The elevation detection sensor 120 detects a protrusion on the lever 121 and coming out of the slide lever 115 on the tray 110, and stops the elevation. This operation timing chart is shown in FIG. The slide lever 115 is movable in the directions of the arrows B and C. The slide lever 115 is slid by changing the length of the feed pressure setting spring 123 so that the feed pressure setting is variable. The adjustment of the paper feeding device 12 makes it easy to change the paper feeding pressure.
In particular, by indicating the pressure according to the type of paper by the position of the slide 115, it is possible to reliably perform the operation even at the user level.

FIG. 6 is an external view when paper is fed to the paper feeding device according to the first, third and fourth aspects. FIG. 7 is a schematic diagram showing the configuration of the sheet feeding device according to the first, third, and fourth aspects. The paper feed pressure setting operation itself is the same as in the above-described embodiment. Here, since the protrusion for detecting the rise is of a dial type 119, the dial is turned and stopped at a predetermined position, so that a multi-step sheet pressure setting can be performed. The adjustment means in the paper feeding device 12 makes it easy to change the paper feeding pressure. In particular, by indicating the pressure according to the type of paper by the position of the dial, the operation can be reliably performed even at the user level.

Next, a paper feeder according to a fourth aspect will be described. The paper feed pressure setting motor 122 is reversely rotated after the rise detection sensor 120 detects the rise and stopped after a predetermined time. This timing chart is shown in FIG.
Shown in This is to compensate for the lag time or the inertia of the motor from the detection by the rise detection sensor 1120 to the stop of the motor because the lag time or the like causes the lag time or the like to rise. This enables fine adjustment even when the user level is operated.

FIG. 9 is a structural view showing the structure of the sheet feeding pressure setting lever according to the fifth and sixth aspects of the present invention. Here, since the optical sensors are mounted on the levers on the movable side of the remaining amount detection sensors 107 and 108,
In order to prevent the sensor from dropping due to an impact or the like at the time of attachment / detachment, a buffer member 130 is provided in the stopper portion. Thus, the impact resistance when pulling out the paper feed tray 110 can be improved at the user level.

Next, the invention according to claim 6 will be described. Here, since the optical sensor is mounted on the movable side lever 121, the harness member 13 to be electrically connected is provided.
Lever 1 to eliminate problems such as pinching while moving
By allowing the harness 132 to pass near the center of rotation 21, disconnection of the harness 132 during operation of the lever 1221 can be prevented.

Next, the invention according to claims 7 and 8 will be described. FIG. 10 is a configuration diagram showing a structure of a finger-feeding-pressure setting slide lever provided with the sheet-feeding-pressure detecting sensor according to the seventh and eighth aspects. Current lever 1
A paper feed pressure detection sensor 131 is provided as a means for detecting the position of the lever 15, and the sensor filler 131 is determined by the position of the lever 115.
'Is pressed and the current paper feed pressure setting position can be detected. By having the paper feed pressure detection sensor 131, the current paper feed pressure setting can be recognized by the machine side and displayed on the operation panel, thereby notifying the user of the current paper feed pressure set value.

[0015]

As described above, in the paper feeding apparatus according to the first aspect, the paper feeding pressure can be easily and reliably changed at the user level by the adjusting means in the paper feeding tray. Therefore, even when the type of paper used in the image forming apparatus is different, by adjusting the paper supply pressure according to the paper, the paper jam in the paper conveyance path in the image forming apparatus and the feeding error from the paper supply tray 1 can be prevented. Can be prevented. Claims 2 and 3
In the paper feeding device described in (1), the paper feeding pressure can be easily and reliably changed at the user level by the adjusting means in the paper feeding tray, and the adjustment can be performed in multiple stages. In the paper feeding device according to the fourth aspect, fine adjustment can be further performed by the operation unit or the like. In the paper feeding device according to the fifth aspect, it is possible to further improve the impact resistance when the paper feeding device is pulled out from the paper feeding tray. In the paper feeding device according to the sixth aspect, it is possible to prevent the disconnection of the harness during the operation of the paper feeding pressure setting lever, and to secure the operational stability of the device. In the paper feeding device according to claim 7, the current paper feeding pressure setting position can be detected on the main body side. In the paper feeding device according to the eighth aspect, the current paper feeding pressure set value can be notified to the user.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus using a sheet feeding device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating a configuration of a sheet feeding device according to an embodiment of the present invention.

FIG. 3 is an external view when a sheet is fed to the sheet feeding device according to the first, second, and fourth aspects.

FIG. 4 is a schematic diagram showing a configuration of a sheet feeding device according to the first, second, and fourth aspects.

FIG. 5 is a chart showing operation timings of the sheet feeding device according to the first and second aspects.

FIG. 6 is an external view when paper is fed to the paper feeding device according to the first, third, and fourth aspects.

FIG. 7 is a schematic diagram showing a configuration of a sheet feeding device according to the first, third, and fourth aspects.

FIG. 8 is a chart showing operation timings of the sheet feeding device according to the fourth embodiment.

FIG. 9 is a configuration diagram showing a structure of a sheet feeding pressure setting lever according to the invention according to claims 5 and 6;

FIG. 10 is a configuration diagram showing the structure of a finger-feeding-pressure setting slide lever provided with the sheet-feeding-pressure position sensor according to the seventh and eighth aspects.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reading unit 2 Discharge roller 3 Fixing unit 4 Photoreceptor 5 Transfer roller 6 Registration roller 7 Toner supply unit 8 Optical writing unit 9 Developing unit 10 Cleaning unit 11 Charging unit 12 Paper supply unit 102 Paper feed tray presence / absence detection sensor 103 Paper roller 104 Friction pad 106 Bottom plate raising lever 107 Remaining amount detection sensor 1 108 Remaining amount detection sensor 2 110 Paper supply tray 112 Remaining amount detection sensor 113 Bottom plate raising lever 115 Paper supply pressure setting slide lever 116 Paper supply tray side fence depth 117 Feed tray fence 118 In front of the feed tray side fence 119 Feed pressure setting dial 120 Elevation detection sensor 121 Lift lever 122 Feed pressure setting motor 123 Feed pressure setting spring 126 Feed pressure lever return spring 127 Feed Paper pressure lever 128 Coupling 129 Ascending shaft 130 Buffer member 131 Feed pressure detection sensor 131 フ ィ ラ ー Sensor filler 132 Ascent sensor harness 134 Feed bottom plate

Claims (8)

[Claims] 1. A sheet feeding apparatus having a mechanism capable of changing a sheet feeding pressure by having a driving means by a motor and a sensor for detecting a rise of a sheet feeding pressure setting lever. A sheet feeding device, comprising: 2. The paper feeding apparatus according to claim 1, wherein the adjusting means adjusts the paper feeding pressure by a slide lever. 3. The paper feeding apparatus according to claim 1, wherein the adjusting means adjusts the paper feeding pressure with a dial-type lever. 4. The paper feeding device according to claim 1, wherein the motor is stopped at a sensor position and then rotated reversely. 5. The sheet feeding device according to claim 1, wherein a buffer member is added to the sheet pressure setting lever. 6. The sheet feeding device according to claim 1, wherein a harness of an upper limit detection sensor passes near a fulcrum of a sheet feeding pressure setting lever. 7. The paper feeding device according to claim 1, wherein the main body can detect a paper feeding pressure set value. 8. The sheet feeding device according to claim 7, wherein the operation unit notifies the sheet feeding pressure.