JPH0126680Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a transfer paper feeding mechanism for feeding a fixed transfer paper out of a copying machine.

[Conventional technology]

As a feeding mechanism for the transfer paper after fixing, the fixing mechanism includes an upper drive feed roller that feeds the transfer paper after fixing to the outside of the machine, and a lower driven feed roller rotated by the drive feed roller. There is a device in which a guide member is provided on the downstream side in the transfer paper conveyance direction, and a guide member is provided between the fixing mechanism and the upper and lower feed rollers to guide the fixed transfer paper from below.

The conventional guide member in such a transfer paper feeding mechanism has a simple flat plate structure on the upper surface for guiding the transfer paper, or a belt conveyor type, and the transfer paper of this guide member The upper and lower feed rollers disposed on the downstream side in the conveyance direction each have a cylindrical roller structure, and the circumferential speed is the same at the center and at both left and right ends in the direction of the rotational axis of the roller. It was hot.

[Problem that the invention attempts to solve]

Therefore, when the transfer paper is guided by the guide member and inserted into the feed roller, the leading edge of the transfer paper hangs downward, making it difficult to insert it into the feed roller smoothly, which causes wrinkles. In extreme cases, there were drawbacks that could cause paper jams. In addition, even if the paper is inserted smoothly into the feed roller, the wrinkles that had previously occurred will be pressed from above and below by the feed roller, which will still significantly reduce the occurrence of wrinkles. This drawback was particularly noticeable in the case of double-sided copying.

The present invention has focused on such conventional drawbacks, and has made it possible to smoothly insert the transfer paper from the guide member to the delivery roller, and to actively remove wrinkles from the transfer paper when the transfer paper is conveyed by the delivery roller. It is an object of the present invention to provide a new and useful transfer paper feeding mechanism that can minimize the occurrence of wrinkles.

[Means for solving problems]

In order to achieve the above object, the present invention has a fixing mechanism that includes an upper driving feed-out roller that feeds the transfer paper after fixing to the outside of the machine, and a lower driven feed-out roller that is rotated by the drive feed-out roller. A transfer paper feeder of a copying machine, wherein a guide member is provided downstream in a transfer paper conveyance direction than the image forming apparatus, and a guide member is provided between the fixing mechanism and the upper and lower feed rollers to guide the fixed transfer paper from below. In the mechanism, the upper surface of the guide member is formed into a curved surface whose widthwise center bulges upward when viewed in the transfer paper conveyance direction, and the driven feed roller is divided into a plurality of pieces in the rotational axis direction, and The transfer paper conveyance surface formed by the divided driven feed-out roller and the drive feed-out roller is configured to substantially follow the upper surface shape of the guide member, and the circumferential speed of the drive feed-out roller of the portion corresponding to the divided driven feed-out roller is is characterized in that it is configured such that the speed increases as the distance from the central divided driven feed roller increases.

[Effect]

According to the above characteristic configuration, the transfer paper after fixing that is fed out from the fixing mechanism is conveyed to the upper and lower feed rollers in a posture along the curved surface of the guide member, and the transfer paper is conveyed to the upper and lower feed rollers in a posture along the curved surface of the guide member. Since the posture of the member is maintained along the curved surface of the member, the so-called stiffness of the paper becomes strong, and the leading edge of the transfer paper is prevented from bending between the guide member and the upper and lower feed rollers, which may lead to paper jams. be done.

The driven feed-out roller is divided into a plurality of parts in the direction of the rotational axis, and the transfer paper conveying surface by the divided driven feed-out roller and the drive feed-out roller is made to substantially follow the top surface shape of the guide member. With this structure, the transfer paper maintained in the curved position is smoothly inserted between the upper and lower feed rollers.

Further, in addition to making the upper surface of the guide member a curved surface and making the transfer paper conveying surface by the divided driven feed-out roller and the drive feed-out roller substantially follow the shape of the upper surface of the guide member, the divided By configuring the circumferential speed of the driving feed-out roller in the portion corresponding to the driven feed-out roller to be faster in the portion farther away from the central divided driven feed-out roller, the transfer paper is conveyed by the upper and lower feed-out rollers. When transferring, both sides of the transfer paper are pulled by the feeding rollers, and the transfer paper is forcibly corrected so as to align with the upper surface of the guide member. When the mechanism is a heating type, the transfer paper immediately after fixing, which is fed out in a wavy shape from the fixing mechanism after heat fixing, is forced to run along the upper surface of the guide member, and the wavy portion is stretched. As a result, wrinkles caused by the corrugation are effectively prevented and sent out of the machine.

〔Example〕

The mode of implementation of the present invention will be described in detail based on illustrative drawings. FIG. 1 shows the outline of the entire electrostatographic copying machine, and in the figure 1 is a photosensitive drum that is rotationally driven. Around the charging mechanism 2,
An exposure mechanism 3, a developing mechanism 4, a transfer mechanism 5, etc. are provided. 6 is a paper feed cassette, and between this cassette 6 and the transfer mechanism 5, there are a plurality of guide plates 7...
A paper feeding roller 8a and a conveying roller 8b are provided to transfer the transfer paper 9 in the cassette 6 to the transfer mechanism 5.
In addition, since the transfer paper of a different size from the paper 9 in the cassette 6 is conveyed to the transfer mechanism 5 by so-called manual feeding,
Other guide plates 10, paper feed rollers 11, and paper feed table 12 are also provided. A suction conveyor belt conveyor 14 is disposed downstream of the photosensitive drum 1 in the conveying direction to convey the transfer paper 9 peeled off from the drum 1 after transfer to a fixing mechanism 13. As shown in the drawings and enlarged in FIG. 3, it is composed of a heating roller 16 containing a heating mechanism 15, and a pressure roller 17 that elastically presses the heating roller 16. Between the fixing mechanism 13 and the transfer paper tray 18, there are a plate-shaped lower guide member 19 and an upper guide member 20 that guide and hold the transfer paper 9 from below, as well as drive feed rollers 21 on the upper side. Lower driven feed-out rollers 22 are provided which are rotated by the drive feed-out rollers 21.

As is clear from FIG. 2, the upper guide member 20 has a substantially flat shape, but the upper surface of the lower guide member 19 has a curved shape in which the center in the width direction bulges upward when viewed in the transfer paper conveyance direction. It is composed of surfaces.
The upper feed-out rollers 21 are integrally driven to rotate by a single drive shaft 23, and the center feed-out roller 21 has a small diameter.
The feed rollers 21, 21 at both the left and right ends are configured to have a large diameter, so that the circumferential speed is faster at both the left and right ends than at the center, and the lower feed rollers 21, 21 having the same diameter 22...
are elastically pressed by the opposing upper feed-out rollers 21, respectively, and as a result, the conveyance surface of the transfer paper 9 by the upper and lower feed-out rollers 21..., 22... conforms to the curvature of the upper guide surface of the guide member 19. It has a nearly curved surface.

Next, the operation will be explained, but since there is no difference from a conventional copying machine until it is conveyed to the fixing mechanism 13 by the belt conveyor 14 after the transfer, the explanation thereof will be omitted. The transfer paper 9 that has reached the fixing mechanism 13 has the toner image fused thereon and reaches the guide member 19 as before, but the guide member 1
Since the upper guide surface of the transfer paper 9 is curved upward, the transfer paper 9 is also forced to curve. When the transfer paper 9 is bent, the leading end side of the transfer paper 9 is connected to the guide member 19.
Even if the transfer paper comes off from the guide member 19, the transfer paper itself
Since the paper is maintained in a posture along the curved surface of the transfer paper, the so-called rigidity of the paper becomes strong and the leading edge side of the transfer paper is prevented from sagging downward. This prevents paper jams between the

Then, the driven feed-out roller 22 is divided into a plurality of parts in the rotational axis direction, and the transfer paper conveyance surface formed by the divided driven feed-out roller 22 and the drive feed-out roller 21 is shaped approximately in the shape of the upper surface of the guide member 19. Since the transfer paper 9 is configured to be aligned along the transfer paper 9, the transfer paper 9 maintained in the curved posture is smoothly inserted between the upper and lower delivery rollers.

Further, the upper surface of the guide member 19 is made into a curved surface,
And, the transfer paper conveyance surface by the divided driven feed-out roller 22 and the drive feed-out roller 21,
In addition to aligning the upper surface shape of the guide member 19, the circumferential speed of the driving feed-out roller 21 in the portion corresponding to the split driven feed-out roller 22 is set to be faster in the portion farther away from the split driven feed-out roller 22 on the central side. By configuring it so that the transfer paper 9 is
When conveyed by the transfer paper 9, both sides of the transfer paper 9 are pulled by the delivery rollers 21 and 22,
The transfer paper 9 is forcibly corrected so as to follow the upper surface of the guide member 19, and especially when the fixing mechanism is of a heating type, the transfer paper 9 may become wavy from the fixing mechanism after heat fixing. The transferred paper 9 immediately after fixing is forcibly moved to the guide member 19.
By stretching the corrugated portion along the upper surface of the sheet, wrinkles caused by the corrugation are effectively prevented and sent out of the machine. At this time, the transfer paper 9 is heated by the fixing mechanism 13, so it looks as if it has been ironed, and even if it has some wrinkles, those wrinkles are forcibly removed. It becomes.

Although three upper and lower feed-out rollers 21..., 22... are shown, the number may be increased beyond this, or the upper feed-out rollers 21... may be configured as a single drum-shaped roller. It's okay to do that.

Furthermore, although a plate-shaped guide member 19 is shown, instead of this plate-shaped guide member, a drum-shaped roller (one or (Multiple books installed side by side)
configuration, or any other structure, such as a belt conveyor type, and
A heating mechanism may be incorporated into this guide member 19 to further improve the ironing effect.

As is clear from the above explanation, the transfer paper feeding mechanism according to the present invention is configured by curving the upper part of the guide member upward, so that the leading edge of the transfer paper is prevented from hanging downward and the transfer paper is The paper can be reliably and smoothly guided and inserted into the feed roller, eliminating wrinkles and paper jams at this location. The feed roller is configured such that its circumferential speed increases toward the left and right ends, so the transfer paper heated by the fixing mechanism is forcibly stretched left and right, as if It will be like being ironed, so even if there are wrinkles,
Those wrinkles will definitely be removed.

[Brief explanation of drawings]

The drawings illustrate an embodiment of the transfer paper feeding mechanism of a copying machine according to the present invention, FIG. 1 is an overall schematic diagram showing the outline of the overall structure, FIG. The figure is a sectional view taken along the line -- in FIG. 2. 9... Transfer paper, 13... Fixing mechanism, 19... Guide member, 21... Drive feed roller, 22...
Driven feed roller.

Claims (1)

[Scope of utility model registration request] An upper driving feed-out roller that sends out the transfer paper after fixing to the outside of the machine, and a lower driven feed-out roller rotated by the drive feed-out roller are provided downstream of the fixing mechanism in the transfer paper conveyance direction, In the transfer paper delivery mechanism of a copying machine, a guide member for guiding the fixed transfer paper from below is disposed between the fixing mechanism and the upper and lower delivery rollers. The driven feed-out roller is formed into a curved surface whose widthwise center bulges upward when viewed in the conveyance direction, and the driven feed-out roller is divided into a plurality of parts in the rotational axis direction, and the transfer is performed by the divided driven feed-out roller and the driven feed-out roller. The paper conveyance surface is configured to substantially follow the upper surface shape of the guide member, and the circumferential speed of the driving feed-out roller in the portion corresponding to the split driven feed-out roller is adjusted to the portion away from the split driven feed-out roller on the central side. 1. A transfer paper feeding mechanism for a copying machine, characterized in that the transfer paper feeding mechanism is configured to be as fast as possible.