JP3735544B2 - Paper feeder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet feeding device, and more particularly, to a sheet feeding device configured to feed sheets by a sheet feeding roller by pressing a sheet stacked and accommodated in a sheet feeding tray against a sheet feeding roller by a pickup lever.
[0002]
[Prior art]
In general, printers such as thermal transfer printers used as output devices for computers, word processors, facsimiles and the like are often used.
[0003]
In such a printer, a paper feed tray that stacks and stores a plurality of paper sheets is detachably mounted, and the uppermost paper is separated from the paper feed tray one by one by a paper feed roller. A paper feeding device is provided for transporting the paper to a paper feed roller and transporting the paper by the paper feed roller. While the sheet is conveyed by the sheet feeding device, desired recording is performed on the sheet by the print head.
[0004]
In this case, the present applicant arranges the hopper plate on the paper feed tray so as to be movable up and down, and stores and stacks the paper on the upper surface of the hopper plate, and the uppermost paper stacked on the paper feed tray. In order to bring the hopper plate into pressure contact with the paper feeding roller, a paper feeding device has been developed in which a pick-up lever for moving the hopper plate upward is provided to be swingable.
[0005]
Then, the paper is separated by rotating the paper feed roller while the hopper plate of the paper feed tray is swung upward by the pickup lever and the uppermost paper of the paper feed tray is pressed against the paper feed roller. Are taken out and conveyed toward the paper feed roller. In the state where the paper is conveyed by the paper feed roller, the pickup lever is swung to lower the hopper plate to release the pressure contact between the paper and the paper feed roller.
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional sheet feeding device, since the swing shaft for swinging the pickup lever is separately provided in the frame of the printer, a space for installing the swing shaft is necessary. There is a problem of increasing the number of parts. In recent years, printers have become particularly compact and low-priced, making it impossible to secure a large installation space and to reduce the cost of parts. The problem is that such a request cannot be met.
[0007]
The present invention has been made in view of the above points, and even with a mechanism for moving the paper in the paper feed tray by the pickup lever, the installation space can be saved and the apparatus can be downsized. At the same time, it is an object of the present invention to provide a paper feeding device that can reduce the number of parts and reduce the cost of parts.
[0008]
[Means for Solving the Problems]
In order to achieve the above-described object, the paper feeding device according to the present invention is provided with a paper feeding roller for picking up a plurality of sheets stacked and accommodated in a paper feeding tray one by one, and is fed by this paper feeding roller. A paper feeding device provided with a paper feed roller for conveying paper, wherein a hopper plate for laminating the paper on the paper feeding tray is arranged to be movable up and down and is laminated on the paper feeding tray. In order to press the uppermost sheet pressed against the sheet feeding roller, a pickup lever for moving the hopper plate upward is provided so as to be swingable, and the pickup lever supports the sheet feeding roller. It is characterized in that it is swingably attached to the drive shaft.
[0009]
According to the present invention, since the pickup lever is swingably attached to the paper feed drive shaft that supports the paper feed roller, it is not necessary to separately provide a swing shaft for swinging the pickup lever. The installation space can be saved, the apparatus can be reduced in size, the number of parts can be reduced, and the part cost can be reduced.
[0010]
According to another aspect of the present invention, in the first aspect of the present invention, a biasing spring is provided for biasing the pickup lever in a direction in which the uppermost sheet stacked on the sheet feeding tray is pressed against the sheet feeding roller. The pickup lever is swung in a direction in which the uppermost portion of the sheet is separated from the sheet feeding roller against a biasing force of the biasing spring by a swing cam.
[0011]
According to the present invention, in the normal state, the pickup lever is pressed against the paper feed roller by the biasing force of the biasing spring, and the pickup lever is attached by the swing cam. The uppermost part of the paper is swung away from the paper feed roller against the biasing force of the spring, so that the paper can be fed properly by the paper feed roller. When the paper is transported by the feed roller, the pressure contact between the paper and the paper feed roller is released, and the proper paper can be transported by the paper feed roller.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3.
[0013]
1 to 3 show an embodiment of a printer to which a paper feeding device according to the present invention is applied. As shown in FIG. 1, the printer of this embodiment includes a bottom plate 1 and both side edges of the bottom plate 1. A frame 3 comprising side plates 2 and 2 erected is provided, and a paper feed drive shaft 4 is rotatably supported at the center of both side plates 2 of the frame 3. A paper feed roller 5 is attached to the middle of the feed drive shaft 4. Further, above the paper feed roller 5, a pressure contact roller 6 pressed against the paper feed roller 5 is rotatably supported. A paper feed drive shaft 7 is rotatably supported at one end portion of both side plates 2 of the frame 3, and two paper feed rollers 8, 8 are provided in the middle of the paper feed drive shaft 7. Is installed.
[0014]
Further, a drive gear 9 that is rotated by a drive motor (not shown) is disposed on one side plate 2 of the frame 3, and a paper feed drive shaft is driven by a gear transmission mechanism (not shown) for the rotational drive force of the drive gear 9. 4 and the paper feed roller 5 can be rotationally driven. The rotational driving force of the drive gear 9 is also transmitted to the paper feed drive shaft 7 by a gear transmission mechanism (not shown), and the paper feed roller 5 and the paper feed roller 5 are rotated by the rotation of the drive gear 9. 8 can also be rotationally driven.
[0015]
Furthermore, in the present embodiment, a pickup lever 10 is swingably disposed below the frame 3. The pickup lever 10 includes a substrate 11 extending along the paper feed drive shaft 4, a lever piece 12 extending from the center of the substrate 11 toward the paper feed roller 5, and both ends of the substrate 11. And a support plate 13 extending in a direction orthogonal to the substrate 11, and supporting the support plates 13 at both ends of the substrate 11 at both ends of the paper feed drive shaft 4. 11 and the lever piece 12 can be swung around the paper feed drive shaft 4. Further, the pickup lever 10 is biased in a direction in which the lever piece 12 swings upward by a biasing spring (not shown), and the support plate 13 positioned on the drive gear 9 side is driven. The arm 14 is attached integrally.
[0016]
The drive gear 9 is provided with a swing cam 15 coaxially, and the tip of the driven arm 14 of the pickup lever 10 follows the outer periphery of the swing cam 15. . The follower arm 14 follows along the outer peripheral surface of the swing cam 15 by the rotation of the swing cam 15 that is rotationally driven together with the drive gear 9, whereby the pickup lever 10 resists the biasing force of the bias spring. It can swing.
[0017]
A recording head (not shown) is disposed inside the frame 3 so that characters, images, and the like can be recorded at predetermined positions on the paper fed by the paper feed roller 5. Yes.
[0018]
A paper feed tray 16 for stacking and storing a plurality of sheets (not shown) is detachably mounted on the side of the paper feed roller 8 of the frame 3. A hopper plate 17 that supports the stacked sheets is arranged to be movable up and down. In the state where the paper feed tray 16 is mounted, the tip end portion of the lever piece 12 of the pickup lever 10 is positioned on the lower surface side of the hopper plate 17 on the paper feed roller 8 side. As shown in FIG. 4, the lever piece 12 swings upward by the biasing force of the biasing spring to move the hopper plate 17 upward, so that the uppermost sheet stored in the sheet feed tray 16 is fed to the sheet feed roller 8. It comes to be pressed.
[0019]
Next, the operation of the present embodiment having the above-described configuration will be described.
[0020]
In the present embodiment, as shown in FIG. 2, the pickup lever 10 is swung upward, and the hopper plate 17 is moved upward by the lever piece 12, so that the uppermost paper stored in the paper feed tray 16 is removed. From the state of being in pressure contact with the paper feed roller 8, the drive gear 9 is driven to rotate the paper feed roller 8 and the paper feed roller 5. The separated paper is taken out and conveyed toward the paper feed roller 5.
[0021]
When the paper is transported to the paper feed roller 5, the recording head performs desired recording on the paper based on predetermined image information while transporting the paper by the paper feed roller 5.
[0022]
At this time, as the drive gear 9 rotates, the swing cam 15 is also driven to rotate, and the driven arm 14 is pushed by the outer peripheral surface of the swing cam 15 to move the pickup lever 10 as shown in FIG. By swinging against the urging force of the urging spring, the upward movement of the hopper plate 17 by the lever piece 12 is released, and the sheet accommodated in the sheet feeding tray 16 is pressed against the sheet feeding roller 8. Is released.
[0023]
Thereafter, recording is continuously performed by the recording head while the sheet is conveyed by the sheet feeding roller 5.
[0024]
Therefore, in the present embodiment, the pickup lever 10 is attached to both ends of the paper feed drive shaft 4 so that the pickup lever 10 is swung around the paper feed drive shaft 4, so that the pickup lever 10 is swung. Therefore, it is not necessary to provide a separate rocking shaft, so that the installation space can be saved, and it is possible to appropriately cope with the downsizing of the apparatus. Further, the number of parts can be reduced, and the cost of parts can be reduced to appropriately cope with the reduction in price.
[0025]
In addition, this invention is not limited to the said embodiment, A various change can be made as needed.
[0026]
【The invention's effect】
As described above, in the paper feeding device according to the present invention, the pickup lever is swingably attached to the paper feed drive shaft that supports the paper feed roller. The installation space can be saved, the apparatus can be reduced in size, and the number of parts can be reduced and the cost of the parts can be reduced. .
[0027]
According to another invention, in a normal state, the pickup lever is pressed against the paper feed roller by the biasing force of the biasing spring, and the pickup lever is moved by the swing cam. Since the uppermost part of the paper is swung away from the paper feeding roller against the urging force of the urging spring, the paper can be fed properly by the paper feeding roller, When the paper is transported by the paper feed roller, it is possible to release the pressure contact between the paper and the paper feed roller and perform proper paper transport by the paper feed roller.
[Brief description of the drawings]
FIG. 1 is a perspective view of a main part showing an embodiment of a paper feeding device according to the present invention. FIG. 2 is a side view showing a normal state in which a pickup lever in the paper feeding device of the present invention is swung upward. FIG. 3 is a side view showing a state where a pickup lever is swung downward by a rocking cam in the paper feeding device of the present invention.
3 Frame 4 Paper feed drive shaft 5 Paper feed roller 7 Paper feed drive shaft 8 Paper feed roller 9 Drive gear 10 Pickup lever 12 Lever piece 14 Drive arm 15 Swing cam 16 Paper feed tray 17 Hopper plate

Claims (2)

A paper feeding device provided with a paper feed roller for picking up a plurality of papers stacked on the paper feed tray one by one and a paper feed roller for transporting paper fed by the paper feed roller A hopper plate for stacking the sheets on the sheet feeding tray is arranged to be movable up and down, and the uppermost sheet stacked on the sheet feeding tray is pressed against the sheet feeding roller. To this end, a pickup lever for moving the hopper plate upward is slidably disposed, and the pickup lever is swingably attached to a paper feed drive shaft that supports the paper feed roller. apparatus. An urging spring is provided for urging the pickup lever in a direction in which the uppermost sheet stacked on the sheet feeding tray is pressed against the sheet feeding roller. 2. The sheet feeding device according to claim 1, wherein the uppermost portion of the sheet is swung in a direction away from the sheet feeding roller against a biasing force of a spring.

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