JP3949351B2 - Paper feeder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper feeding device used in an image forming apparatus such as a copying machine, a facsimile machine, a printer, or a multifunction machine. More specifically, the present invention relates to a paper feeding pressure that adjusts the paper feeding pressure according to the type of paper used in the image forming apparatus. This invention relates to a paper device.
[0002]
[Prior art]
In recent years, in printing machines, laser printers, and other devices, printing needs for postcards, OHP and other special purpose papers are increasing. On the other hand, in order to meet such a demand, stabilization of the sheet feeding device performance is an essential issue. In a sheet feeding apparatus such as a friction pad separation method, the sheet feeding pressure has a great influence on sheet feeding performance, and it can be said that stabilization of sheet feeding pressure, that is, sheet feeding performance is stabilized. However, for applications such as the above-mentioned special paper, it is possible to cope with problems such as non-feeding by making the paper feed pressure variable.
[0003]
Therefore, in order to make the paper feed pressure variable, for example, in Japanese Patent Laid-Open No. 6-127710, the vertical position of the pressure spring for pushing up and the lower end of the pressure spring is adjusted to the bottom plate that supports the paper. A paper feed cassette provided with adjusting means has been proposed. Japanese Patent Laid-Open No. 5-58472 includes an intermediate plate on which sheets are stacked, and a pressurizing unit that pressurizes the sheet to the rotary feeding body. The pressurizing unit includes an intermediate plate pressurizing arm and an intermediate plate. There have been proposed a sheet feeding apparatus and an image forming apparatus having a spring for urging the rotary feeding body and an elastic force changing means for changing the elastic force of the spring. Further, in Japanese Patent Application Laid-Open No. 7-237760, the pressure contact force changing means for changing the pressure contact force of the sheet pressure contact means is a sheet feeding in which the control means adjusts the pressure contact force from the detection results of the sheet size detection means and the sheet residual detection means. An apparatus and an image forming apparatus including the apparatus have been proposed. In Japanese Patent Application Laid-Open No. 8-73056, a sheet feeding pressure correcting unit that automatically maintains a sheet feeding pressure by a pressing unit that pressurizes a sheet to a rotary feeding body in accordance with the remaining amount or size of stacked sheets. A sheet feeding apparatus and an image forming apparatus including the above have been proposed.
[0004]
[Problems to be solved by the invention]
However, the above-described paper feed cassette has the following problems. The paper feed cassette disclosed in Japanese Patent Laid-Open No. 6-127710 has a paper feed pressure adjusting means in the tray, but there is a problem that the adjustment is not simple and can only be performed by a special engineer such as a serviceman. In addition, the sheet feeding apparatus and the image forming apparatus disclosed in Japanese Patent Laid-Open No. 5-58472 have a sheet feeding pressure adjusting unit. However, the adjustment is not simple and there is a problem that only a special engineer such as a service person can perform the adjustment. . Further, the paper feeding device disclosed in Japanese Patent Laid-Open No. 7-237760 and an image forming apparatus including the same, and the paper feeding device and image forming apparatus disclosed in Japanese Patent Laid-Open No. 8-73056 have a paper feeding pressure adjusting means in the tray or the main body. However, there is a problem that it is difficult for the user to easily operate, because the user arbitrarily changes the cost, and the operability is increased due to the addition of the hardware SW or the addition of the software SW.
[0005]
Accordingly, the present invention has been made in view of the above-described problems, and an object of the present invention is to easily change the paper feed pressure at the user level and to easily stabilize the paper feed performance. It is an object of the present invention to provide a paper feeding device that can perform the above processing. It is another object of the present invention to provide a paper feeding device that can easily determine the current paper feeding pressure state at a glance. Another object of the present invention is to provide a sheet feeding device that makes it possible to easily determine the current sheet feeding pressure state at a glance, and a multi-stage pressure adjustment by using a dial type. . Another object of the present invention is to provide a paper feeding device that can be finely adjusted by an operation unit or the like. It is another object of the present invention to provide a paper feeding device that improves impact resistance when the tray is pulled out. Another object of the present invention is to provide a paper feeding device that improves operational stability. Another object of the present invention is to provide a paper feeding device that can detect the current pressure setting value. Another object of the present invention is to provide a paper feeding device that can notify the user of the current pressure setting value.
[0006]
[Means for Solving the Problems]
In order to achieve the above object , a sheet feeding device according to the present invention is a sheet feeding device that conveys sheets, and includes a driving unit that raises a bottom plate, a slide lever provided on a tray, and a position of the slide lever. According to the position of the slide lever detected by the sensor, the sheet feeding pressure can be changed by changing the position at which the driving means stops raising the bottom plate .
According to another aspect of the present invention, there is provided a sheet feeding device including a driving unit that raises a bottom plate, a dial lever provided on a tray, and a sensor that detects a position of the dial lever. The feeding pressure can be changed by changing the position where the driving means stops raising the bottom plate in accordance with the position of the dial lever detected by.
Further, the paper feeding device of the present invention further reverses the rotation after stopping the motor at the position detected by the sensor .
Further, the sheet feeding device of the present invention can detect the set value of the sheet feeding pressure on the main body side.
In the sheet feeding device of the present invention, the sheet feeding pressure is further notified by the operation unit on the main body side .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus using a paper feeding device according to an embodiment of the present invention. Here, specifically, an 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 feed tray 110, a registration roller 6, a photoreceptor 4, a developing unit 9, The process unit includes a charging unit 11, a cleaning unit 10, the fixing unit 3 including a fixing roller and a pressure roller, a paper discharge roller pair 2, and an optical writing unit 8.
Here, an image forming operation 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 as the charging unit 10. Next, the optical writing unit 8 irradiates the photosensitive member 4 with laser light corresponding to image information from the outside through the exposure opening to form a latent image. Then, the developing roller containing the fixed magnet is rotated, and a developer layer imparted with triboelectric charge by a developer regulating member (not shown) is formed on the surface of the developing roller, and is formed by the photoreceptor and the developing roller. Supplied to the development area. Next, the developer is transferred to the photoconductor 4 in accordance with the latent image and 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 photosensitive member 4 to a sheet. Thereafter, the cleaning unit 11 scrapes and stores the developer remaining on the photoconductor by an elastic cleaning blade provided in contact with the photoconductor 4. The paper in the paper feed tray 110 is conveyed 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.
[0008]
Here, with reference to the paper feeding device in FIG. 2, the operation of paper conveyance will be described in detail. A paper feed tray 110110 that stores paper cut into a predetermined size such as A4 and B5, a paper feed roller 103 that sequentially takes out the paper one by one from the paper feed tray 110, and a relay transport driving roller that transports the paper And a relay conveying driven roller, a bottom plate 134 supported by a rotation fulcrum on the upstream side in the sheet conveying direction and biased toward the sheet feeding roller 103 side, and attached to the upper surface of the bottom plate 134 and pressed against the sheet feeding roller 103. The friction pad 104 is configured. The friction pad 104 is positioned on the downstream side in the conveyance direction of the sheet conveyed by the sheet feeding roller 103 and is elastically brought into contact with the outer peripheral surface of the sheet feeding roller 103. The sheet is taken out from the sheet feeding tray 110 by the sheet feeding roller 103 and sent to the press contact portion between the sheet feeding roller 103 and the friction pad 104. The friction pad 104 separates and feeds sheets one by one using a difference in frictional force between the sheet and the sheet feeding roller 103, between the sheet and the sheet, and between the sheet and the friction pad 104. At this time, the paper separation method may be any method such as a separation claw method or a friction roller method. The sheet separated into one sheet is conveyed from the sheet feeding tray 110 by the sheet feeding roller 103, reaches the relay driving unit, and is conveyed to the driving unit by the relay conveying driving roller and the relay conveying driven roller. Here, the timing for transferring the toner image is synchronized and conveyed to the transfer roller 5 by the registration driving roller and the registration driven roller. The same is true for manual sheet feeding with respect to sheet conveyance.
Thereafter, the sheet that has received the transfer of the toner image is conveyed to the fixing unit 3. The fixing unit 3 includes a pressure roller and a fixing roller having a built-in heater. Then, the transferred toner image is fixed by applying heat and pressure to the passing paper. The sheet is conveyed by the discharge roller 2 and discharged to a sheet discharge unit outside the image forming apparatus through the discharge port.
[0009]
FIG. 3 is an external view when paper is fed to the paper feeding device of the present invention . FIG. 4 is a schematic diagram showing the configuration of the paper feeding device of the present invention . As described above, the paper on the paper feed tray 110 is fed, but here, when the paper feed tray 110 is set, it is connected to the raising lever 106 for raising the bottom plate 134 of the paper feed tray 110. The ascending shaft 129 and the coupling 128 are engaged with each other. When the detection sensor 102 detects that the paper feed tray 110 is set, the paper feed pressure setting motor 122 rotates in the arrow A direction. As a result, the paper feed pressure setting spring 123 is extended by engaging with the lever 121. The ascending detection sensor 120 is on the lever 121 and detects a protrusion protruding on the sliding lever 115 on the tray 110 to stop the ascent. This operation timing chart is shown in FIG. The sliding lever 115 can be moved in the directions of arrows B and C. By changing the length of the sheet feeding pressure setting spring 123, the sliding lever 115 is slid to change the sheet feeding pressure setting. The adjusting means of the paper feeding device 12 makes it easy to change the paper feeding pressure. In particular, the pressure corresponding to the type of paper is indicated by the position of the slide 115, so that it can be reliably performed at the user level.
[0010]
FIG. 6 is an external view when paper is fed to the paper feeding device of the present invention . FIG. 7 is a schematic diagram showing the configuration of the paper feeding device of the present invention . The sheet feeding pressure setting operation itself is the same as in the above-described embodiment. Here, since the protrusion for detecting the rise is of the dial type 119, a multi-stage paper feed pressure setting can be performed by turning the dial and stopping at a predetermined position. The adjusting means in the paper feeding device 12 makes it easy to change the paper feeding pressure. In particular, the pressure corresponding to the type of paper is indicated by the position of the dial, so that it can be reliably performed at the user level.
[0011]
Next, the present invention is characterized in that the 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. This is to compensate for the lag time or the inertia of the motor from the detection by the rise detection sensor 1120 until the motor is stopped, and the lag time or the like is increased. Thereby, even when the user level is operated, fine adjustment is possible.
[0012]
FIG. 9 is a block diagram showing the structure of the paper feed pressure setting lever 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, the buffer member 130 is provided at the stopper portion in order to prevent the sensor from dropping due to an impact or the like when the paper feed tray 110 is attached or detached. Provide. Thus, it is possible to improve the impact resistance when the paper feed tray 110 is pulled out at the user level.
[0013]
Next, according to the present invention , since the optical sensor is mounted on the movable lever 121, the harness 132 passes through the vicinity of the rotation center of the lever 121 in order to eliminate problems such as the harness member 132 to be electrically coupled being sandwiched while moving. By doing so, disconnection or the like of the harness 132 can be prevented during the operation of the 1221 lever.
[0014]
FIG. 10 is a block diagram showing the structure of a finger pressure setting slide type lever provided with a paper feed pressure detection sensor of the present invention . A paper feed pressure detection sensor 131 that is a means for detecting the current position of the lever 115 is provided, and the sensor filler 131 ′ is pushed by the position of the lever 115 to enable detection of the current paper feed pressure setting position. By having this paper feed pressure detection sensor 131, the machine side recognizes the current paper feed pressure setting and displays it on the operation panel, thereby making it possible to inform the user of the current paper feed pressure setting value.
[0015]
【The invention's effect】
As described above, in the sheet feeding device of the present invention, the sheet feeding pressure can be easily and reliably changed at the user level by the adjusting means in the sheet feeding tray. Therefore, even when the type of paper used in the image forming apparatus is different, by adjusting the paper feed pressure according to the paper, jams in the paper conveyance path in the image forming apparatus and feed mistakes from the paper feed tray can be prevented. Can be prevented. Further, in the sheet feeding device of the present invention, the sheet feeding pressure can be easily and reliably changed at the user level by the adjusting means in the sheet feeding tray, and can be adjusted in multiple stages.
In the paper feeding device of the present invention, it is possible to make fine adjustment with the operation unit or the like. In the paper feeding device of the present invention, it is possible to further improve the impact resistance when pulling out from the paper feeding tray. In the paper feeding device of the present invention, it is further possible to prevent disconnection of the harness during the operation of the paper feeding pressure setting lever, and to ensure operational stability as a device. In the paper feeding device of the present invention , the current paper feed pressure setting position can be detected on the main body side. In the paper feeding device of the present invention , the current paper feed pressure setting 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 paper feeding device according to an embodiment of the present invention.
FIG. 2 is a schematic diagram illustrating a configuration of a paper feeding device according to an embodiment of the present invention.
FIG. 3 is an external view when paper is fed to the paper feeding device of the present invention .
FIG. 4 is a schematic diagram illustrating a configuration of a sheet feeding device according to the present invention .
FIG. 5 is a chart showing the operation timing of the sheet feeding device of the present invention .
FIG. 6 is an external view when paper is fed to the paper feeding device of the present invention .
FIG. 7 is a schematic diagram illustrating a configuration of a sheet feeding device according to the present invention .
FIG. 8 is a chart showing the operation timing of the sheet feeding device of the present invention .
9 is a block diagram showing a structure of a setting lever of sheet feeding pressure force of the present invention.
10 is a block diagram showing the structure of the paper finger pressure settings sliding lever providing a sheet feeding pressure position sensor of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Reading unit 2 Paper discharge roller 3 Fixing unit 4 Photoconductor 5 Transfer roller 6 Registration roller 7 Toner replenishment unit 8 Optical writing unit 9 Development part 10 Cleaning part 11 Charging part 12 Paper feed part 102 Paper feed tray presence detection sensor 103 Supply Paper roller 104 Friction pad 106 Bottom plate raising lever 107 Remaining amount detection sensor 1
108 Remaining amount detection sensor 2
110 Feeding tray 112 Remaining amount detection sensor 113 Bottom plate raising lever 115 Feeding pressure setting slide lever 116 Feeding tray side fence back 117 Feeding train fence 118 Feeding tray side fence front 119 Feeding pressure setting dial 120 Raising detection Sensor 121 Raising lever 122 Feeding pressure setting motor 123 Feeding pressure setting spring 126 Feeding pressure lever return spring 127 Feeding pressure lever 128 Coupling 129 Lifting shaft 130 Buffer member 131 Feeding pressure detection sensor 131 ′ Sensor filler 132 Raising detection Sensor harness 134 Paper feed bottom plate

Claims (5)

  In a paper feeder that transports paper,
  Driving means for raising the bottom plate;
  A sliding lever provided on the tray;
  A sensor for detecting the position of the sliding lever;
  The sheet feeding pressure can be changed by changing the position where the driving means stops raising the bottom plate according to the position of the sliding lever detected by the sensor.
  A paper feeder characterized by that.   In a paper feeder that transports paper,
  Driving means for raising the bottom plate;
  A dial lever on the tray;
  A sensor for detecting the position of the dial lever;
  The feeding pressure can be changed by changing the position at which the driving means stops raising the bottom plate according to the position of the dial lever detected by the sensor.
  A paper feeder characterized by that. In the paper feeding device according to claim 1 or 2,
The sheet feeding device, wherein the motor is stopped at the position detected by the sensor and then reversely rotated. The paper feeding device according to any one of claims 1 to 3,
The sheet feeding apparatus, wherein the main body side can detect the set value of the sheet feeding pressure . The sheet feeding device according to claim 4,
A sheet feeding device that notifies sheet feeding pressure by an operation unit on the main body side .

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