JP3656969B2 - Paper feeder for image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying machine, a printer, or a plotter, and more particularly to a recording material feeding apparatus thereof.
[0002]
[Prior art]
In the known image forming apparatus as described above, a recording material that has been cut into a predetermined size in advance and a long recording that is wound in a roll shape and cut into the predetermined size after the recording is completed. Proposals have been made that materials can be appropriately selected and used.
[0003]
It is well known that the apparatus capable of selectively feeding cut paper and roll paper as described above may have a single conveyance path or a plurality of conveyance paths. These will be briefly described below with reference to “FIG. 7” and “FIG. 8”.
[0004]
These drawings are schematic side sectional views showing a recording material feeding portion of the image forming apparatus, and FIG. 7 is for feeding cut paper and roll paper through the same conveyance path. A cover 9 is disposed on the operator side of the image forming apparatus, and a recording material 11 wound in a roll shape is accommodated therein, and the upper surface of the cover 9 is for feeding cut paper. It is the base of.
[0005]
The end portions of the guide plate 12 and the guide 8 arranged in the vicinity of the cover 9 are arranged close to each other to form a conveyance path 26. The cut paper 22 advances in the direction indicated by the arrow A, and the leading end of the roll paper unwound from the roll paper 11 advances in the direction indicated by the arrow B, and is supported by the drive roller 1 and the holder 4 via the conveying path 26 and the spring 5. Thus, the belt runs while being sandwiched by the conveying roller 2 in pressure contact with the driving roller 1, and reaches the image forming position including the recording head 14.
[0006]
“FIG. 8” shows the roll paper 11 transport path and the cut paper 22 that are separated and formed at an upstream position. The separation member 10 is disposed between the guide plate 12 and the guide 8 that form the above-described conveyance path 26, and the conveyance path 26 is disposed between the upper surface of the member 10 and the guide plate 12, and the lower surface of the separation member 10. A conveying path 27 is formed between the guide 8 and the guide 8.
[0007]
The cut sheet 22 is supplied to the driving roller 1 through the conveyance path 26 in the direction of arrow A and further reaches the image forming portion. A pair of rollers 3a driven by a driving source 25 is disposed at an appropriate position on the conveyance path 27, and the rolled paper roll is sandwiched between the rollers and travels through the conveyance path 27 and the drive roller 1. To the forming device. When the roll paper is not used, the roller pair 3a holds its tip and waits until the next activation.
[0008]
In general, in this type of image forming apparatus, it is indispensable that the recording material to be supplied does not incline while in progress. In particular, an apparatus as shown in FIG. When they are used alternately, it is necessary to adjust the position of the leading edge of the recording material each time, which is troublesome and inevitably affects the work efficiency.
[0009]
Further, the means for gripping the leading edge of the roll paper of the apparatus shown in FIG. 8 with a roller is required to have a high degree of accuracy in the single item of the roller, the mounting position accuracy, and the like, resulting in a cost problem. Furthermore, there are means for providing a plurality of conveyance paths for each cut paper and roll paper, and conveying the recording material by each drive source, but such a thing naturally has the above-mentioned problems and is preferable. Absent.
[0010]
[Problems to be solved by the invention]
The present invention has been made to cope with such a situation. Particularly in an image forming apparatus using a large-format recording material, when conveying cut paper, the tip of the roll paper is securely held, and the roll paper is removed. An object of the present invention is to realize a recording material feeding apparatus capable of selectively transporting cut paper and roll paper by opening it with a simple configuration, high accuracy, and low cost.
[0011]
[Technical means for solving the problem and its operation]
In order to achieve the above object, the present invention comprises a driving roller and a roller that is elastically swingable in the contact / separation direction. After passing through a facing position between the driving roller and the roller, the driving roller is provided. In a paper feeding device of an image forming apparatus having a single conveyance path for conveying a recording material along a roller, a cut paper conveyance path and a roll paper conveyance path are provided upstream of the facing position in the recording material conveyance direction. A sheet feeding device (1) of an image forming apparatus, which is provided with a switching member for selectively guiding cut paper or roll paper to the one conveyance path, or
In the above (1), the swingable roller is separated from the drive roller when the cut paper is conveyed, and a cut paper path is formed between the drive roller and the roller. A sheet feeding device (2) of the image forming apparatus, further comprising a switching member that moves inward in the radial direction to form a roll paper path between the driving roller and the roller, or
In the above (2), the means for moving at least a part of the replacement member inward in the radial direction from the outer peripheral surface of the drive roller includes at least one annular groove formed in the outer peripheral direction of the drive roller, A sheet feeding device (3) of the image forming apparatus, comprising: at least one convex portion provided on the switching member so as to be engaged and disengaged with
In the above (2), the sheet feeding device of the image forming apparatus is characterized in that when the cut sheet is conveyed, the convex portion of the switching member that presses the swingable roller constitutes the leading end gripping portion of the roll paper that follows. (4) or
In the above (4), the sheet feeding device (5) of the image forming apparatus, wherein the roller contacts with the convex portion of the switching member, and a high friction portion is formed on the roller.
In the above (5), the sheet feeding device (6) of the image forming apparatus, wherein the portion of the convex portion of the switching member that contacts the roller is formed on a high friction surface, or
In any one of the above (1) to (6), a plurality of rollers are provided in the circumferential direction of the driving roller so as to selectively form the cut paper conveyance path and the roll paper conveyance path in contact with and away from the driving roller. This is a sheet feeding device (7) of the image forming apparatus.
[0012]
With such a configuration, it is possible to provide a paper feeding device of an image forming apparatus that can selectively transport cut paper and roll paper to an image forming portion with a simple configuration, high accuracy, and low cost.
[0013]
[Explanation of Examples]
FIG. 1 is a perspective view of a main part of a plotter to which the present invention is applied, particularly showing a recording material conveyance site. The roll paper in the cover 9 or the cut paper placed on the cover 9 advances from the lower right side to the upper left side in the figure, and advances along the driving roller 1 driven by the driving motor 30, and an image forming part (not shown). Shall be reached. A holder 4 (to be described later) is disposed along the outer periphery of the driving roller 1, and the recording material that has reached the position of the driving roller 1 is thereby advanced along the roller.
[0014]
A plurality of grooves 18 are formed in the drive roller 1 at positions corresponding to the width direction lengths of recording materials of various sizes, and a control roller 3 is disposed at a position facing the grooves 18 as will be described later. A oscillating roller base 6 provided with is elastically in contact with the drive roller 1.
[0015]
As shown in FIG. 1, a switching lever 31 for switching the illustrated right end cut sheet conveyance mode and roll sheet conveyance mode of the apparatus main body is provided. The transfer mode is switched.
[0016]
FIG. 2 is a side sectional view of the vicinity of the drive roller 1 and the conveyance paths 26 and 27 shown at a position corresponding to one groove 18 of the drive roller 1 of the apparatus main body. It is assumed that the cut paper advances along the conveyance path 26 in the direction of the arrow A, and the roll paper advances along the conveyance path 27 in the direction of the arrow B and contacts the driving roller 1.
[0017]
FIG. 3 is a perspective view of the roller table 6. The roller base 6 is pivotally attached by a shaft 29, and a control roller 3 is provided at one end of the roller base 6, and the roller 3 is a roller fixed to the roller base 6 in the illustrated case. It consists of two rollers 34 rotatably arranged on the shaft 33 and a non-rotating roll paper control body 35 made of a high friction material such as rubber between them. The control body 35 can have various outer shapes, but it is preferable that the outer periphery thereof is inside (as viewed in the radial direction) the outer periphery of the roller 34. Further, the other end of the roller base 6 is engaged with the other end of the spring 7 which is engaged with one end of the roller body 6 at an appropriate position of the apparatus body. Rotation habits are given so as to make pressure contact.
[0018]
A convex portion 19 is formed in a comb-like shape at a position corresponding to the groove 18 of the driving roller 1 at an end portion of the switching member 10 corresponding to the downstream side of each of the conveying paths 26 and 27. The width of the convex portion 19 is such that this portion can freely enter and retreat into the groove 18. Further, as can be seen from FIG. 2, the position of the convex portion 19 is set so that the roller 3 is in contact with the driving roller 1 and is aligned with the control body 35.
[0019]
The positional relationship among the roller 1, the switching member 10, and the roller 3 will be described with reference to FIG. When the switching member 10 is in the position shown in the drawing, the convex portion 19 of the member enters the groove 18 of the driving roller 1, so that the driving roller 1 and the roller 3 come into contact with each other as shown in the drawing, and the conveying path 27, the roll paper traveling in the direction of arrow B is sandwiched between the roller 1 and the roller 3 to proceed.
[0020]
When the switching member 10 rotates a predetermined amount counterclockwise from the illustrated position, the convex portion 19 of the roller base 6 abuts against the control body 35 of the roller 3 to hold the leading end of the roll paper, and the spring 7 Against the action, the convex portion 19 and the roller 3, and thus the switching member 10 and the roller base 6 rotate, and the convex portion 19 escapes from the groove 18, and the conveyance path 26 is between the guide plate 12 and the upper surface of the switching member 10. Is formed. If the cut sheet is supplied in the arrow A direction in this state, the cut sheet is conveyed by the driving roller 1 and a conveyance roller (not shown) and is conveyed to an image forming portion (not shown). When converting from the roll paper conveyance mode to the cut paper conveyance mode, in order to ensure the holding of the roll paper tip, the portion of the convex portion 19 that contacts and rubs against the control body 35 of the roller 3 is denoted by reference numeral 20. It is preferable to provide a high friction surface by applying appropriate means such as rubber lining and sandblasting.
[0021]
Next, the cut sheet conveyance mode and the roll sheet conveyance mode will be described with reference to FIG. 4 and FIG. When the switching lever 31 (refer to “FIG. 1”) is rotated to the cut sheet conveyance mode position, as described above, the switching member 10 is rotated counterclockwise as viewed in FIG. The conveyance path through which the protruding portion 19 formed on the switching member 10 is removed from the groove 18 and the cut sheet 22 can be advanced in the direction of the arrow A between the switching member 10 and the guide plate 12. 26 is formed.
[0022]
In this case, when there is already set roll paper, the roll paper is rewound to the off position of the cut paper feed sensor 16 before the transport path 26 is formed, and the leading end is between the convex portion 19 and the roller 3. Retreat to the position where it is pinched.
[0023]
As described above, the switching member 10 having the convex portion 19 and the roller base 6 on which the roller 3 is arranged rotate counterclockwise, so that the control member 35 of the roller 3 and the convex portion 19 are sandwiched. The leading edge of the roll paper is maintained as it is. In this state, the sensor 16 is turned on to start the recording material conveyance sequence.
[0024]
When the switching lever 31 of the apparatus main body is switched to the roll paper transport mode side, the switching member 10 is thereby rotated clockwise to take the position shown in FIG. At this position, the convex portion 19 enters the groove 18 of the driving roller 1, and the leading end portion of the roll paper sandwiched between the roller 3 and the convex portion 19 is held by the roller 3 and the driving roller 1. It becomes. At the same time, a roll paper conveyance path 27 is formed between the lower surface of the switching member 10 and the guide 8.
[0025]
When the switching lever 31 is set to the roll paper mode as described above, a switching completion signal is transmitted to the driving motor 30 by the switching detection sensor 32, the driving roller 1 is activated, and a roll paper setting sequence is started.
[0026]
When roll paper is not set, after the transport path 27 is formed, the roll paper is transported, and when the leading edge reaches the paper sensor 17, the recording material setting sequence is started by the sensor.
[0027]
FIG. 6 is a schematic sectional side view of a main part of a plotter storing two roll papers. In the illustrated apparatus, parts corresponding to those of the apparatus of the embodiment are denoted by the same reference numerals, and description thereof will be omitted unless necessary.
[0028]
As shown in the figure, roll papers 11a and 11b are accommodated in the sleeping cover 9. The roll paper 11a includes a roller base 6a having a roller 3a, switching members 10a and 17a, and the roll paper 11b. A roller base 6b having a roller 3b, a switching member 10b, a sensor 17b, and the like are arranged correspondingly. By the same operation as in the above-described embodiment apparatus, the first roll paper 11a can be selectively conveyed by the roller table 6a and the second roll paper 11b by the roller table 6b and the like.
[0029]
When the first roll paper transport path functions, the cut paper transport path and the second roll paper transport path do not function, and when the second roll paper transport functions, the cut paper transport path does not function. Further, when the cut sheet conveyance path functions, the switching members 10a and 10b both take counterclockwise positions, the first and second roll sheet conveyance paths are shielded, and the cut sheet conveyance path 26 is It is formed.
[0030]
In the roll paper transport mode, a switching lever (not shown) is brought to a preset position, and one of the switching members is brought close to the drive roller, thereby transporting the transport path 27a for the roll paper 11a or the roll paper 11b. A path 27b is selectively formed. It will be easily understood that the recording material conveyance sequence of the cut paper, the first roll paper, and the second roll paper can be performed in the same manner as in the above-described embodiment apparatus.
[0031]
【The invention's effect】
As described above, according to the present invention, in the paper feeding device of the image forming apparatus in which the recording material is gripped by the driving roller and the roller in contact with the driving roller and the recording material is conveyed along the driving roller, A cut paper conveyance path and a roll paper conveyance path are formed on the upstream side of the roller contacting the driving roller as viewed in the material traveling direction so that they can be selectively used depending on the recording material. Therefore, a plurality of types of recording materials can be reliably conveyed with a small, simple and low-cost configuration.
[0032]
Also, when transporting cut paper, the leading edge of the roll paper in the roll paper transport path can be firmly held during standby, so there is no need to pay attention to preventing skewing of the recording material each time it is used. There is also a remarkable effect in improving workability.
[Brief description of the drawings]
FIG. 1 is a perspective view of an essential part of an image forming apparatus to which the present invention is applied. FIG. 2 is an enlarged side sectional view showing a sheet feeding portion. FIG. 3 is a perspective view showing a roller stand configuration. FIG. 5 is a side sectional view showing a roll paper conveyance mode of the apparatus shown in FIG. 6. FIG. 6 is a side sectional view showing a conveyance part of an image forming apparatus according to another embodiment. 7] A sectional side view showing a conveyance part of a known image forming apparatus. [FIG. 8] A sectional side view showing a conveyance part of another known image forming apparatus.
DESCRIPTION OF SYMBOLS 1 Drive roller 2 Conveyance roller 3 Control roller 4 Holder 5, 7 Spring 6 Roller base 8 Guide 9 Cover 10 Switching member 12 Guide plate 14 Recording head 16, 17 Sensor 18 Groove 26, 27 Conveyance path

Claims (4)

A driving roller and a roller swingable in the contact / separation direction are provided on the driving roller, and after passing through a position where the driving roller and the roller are opposed to each other, one conveying path is formed for conveying the recording material along the driving roller. In the sheet feeding device of the image forming apparatus,
A cut sheet conveyance path and a roll paper conveyance path are provided upstream of the opposing position in the recording material conveyance direction , and a switching member that selectively switches between the cut paper conveyance path and the roll paper conveyance path is provided.
The drive roller is formed with a groove having a predetermined width extending in the outer circumferential direction on the outer circumferential surface thereof.
The switching member is formed with a convex portion that enters and exits the groove,
When transporting cut paper, the roller is separated from the drive roller and the convex portion is allowed to escape from the groove to form a cut paper path between the drive roller and the roller ,
When conveying roll paper, the paper feeding device is characterized in that the convex portion is moved into the groove to block the cut paper conveyance path, and a roll paper path is formed between the driving roller and the roller. . The paper feeding device according to claim 1 , wherein when the cut paper is conveyed, a leading end of the roll paper is held between the convex portion and the roller . The sheet feeding device according to claim 2, wherein a portion of the roller that contacts the convex portion is formed with a high friction portion . The contact part which contacts the said convex part among the said rollers is located inside the outer periphery of the non-contact part which does not contact the said convex part among the said rollers. Paper feeder.

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