Paper output mechanism

Abstract

A paper output mechanism includes: a roller pair composed of a first roller and a second roller travelable around the first roller and configured, when the second roller is in a first position, to output a piece of paper to a paper placement part by pinching the piece of paper between the first and second rollers and driving at least one of the first and second rollers into rotation with an actuator; and a roller position changing mechanism for switching the second roller between the first position and a second position located closer to the paper output side than the first position. When the trailing edge of the piece of paper is sent out to the paper placement part, the roller position changing mechanism changes the second roller from the first position to the second position.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority under 35 USC 119 to Japanese Patent Application No. 2008-018213 filed on Jan. 29, 2008, the entire contents of which are incorporated herein by reference.BACKGROUND[0002]The techniques disclosed in this specification relate to paper output mechanisms for outputting a piece of paper conveyed to the terminal end of a paper conveyance path from the terminal end thereof to a paper placement part disposed below the terminal end.[0003]It is so far well known that in printers such as for photo printing systems their printer body is internally provided with a paper conveyance path along which paper is conveyed. The terminal end of the paper conveyance path is located in the vicinity of a paper output port in the printer body. A piece of paper (printed piece of paper) conveyed to the terminal end of the paper conveyance path is output from the terminal end through the paper output port by a paper output mechanism, s...

AI Technical Summary

Benefits of technology

[0005]The paper placement part is generally disposed below the terminal end of the paper conveyance path, whereby the leading end of each piece of paper sent out from the terminal end towards the paper placement part sags by gravity and is output while sliding on the top surface of the paper placement part or the top surface of a piece of paper already placed on it. Therefore, after the trailing edge of the piece of paper is sent out, the paper stop point is not fixed owing to the frictional resistance acting on the leading edge thereof and the paper placement point varies with each output piece of paper. In particular, when a long rolled paper web is cut in a given length of piece and then output, the long paper web is normally rolled with the printing surface to be printed coming outside and the printed and cut piece of paper is output with the printed surface facing up. Therefore, the output piece of paper has a curl with the lengthwise middle thereof rising up from both ends thereof owing to a core set of the paper web rolled around a core. This increases variations in the paper placement point. If the paper placement point varies in this manner, this increases the likelihood that, particularly when pieces of paper are conveyed by a belt conveyer to transfer them such as to a collection part, the transfer is disrupted.

[0006]To cope with the above problem, if the output speed of the piece of paper is increased to some degree, the paper stop point, i.e., the paper placement point, can be stabilized.

[0008]The present invention has been made in view of the foregoing points and, therefore, an object of the invention is to provide a paper output mechanism that can stabilize the paper placement point on the paper placement part even if it is difficult to increase the output speed of the piece of paper.

[0010]With the above configuration, in sending out the trailing edge of each piece of paper to the paper placement part, the second roller moves from the first position to the second position. Therefore, in conjunction with the movement of the second roller, a force in the paper output direction is applied from the second roller to the trailing edge of the piece of paper, whereby the piece of paper is accelerated in the paper output direction. Thus, after the trailing edge is sent out, the piece of paper can easily move against the frictional force acting on the leading edge thereof. Therefore, even if the output speed of the piece of paper is low in sending out part thereof other than the trailing edge, the output speed is increased in sending out the trailing edge thereof, whereby the paper placement point on the paper placement part can be stabilized. Furthermore, since the output speed of the piece of paper is decreased in sending out the part thereof other than the trailing edge, ink adhering to the printing surface of the piece of paper, for example, can be certainly dried.

[0012]Thus, the traveling stroke of the second roller from the first position to the second position can be increased to increase the output speed of the trailing edge of the piece of paper as much as possible. Furthermore, when the second roller is in the first position, if the piece of paper has a curl due to a core set formed by rolling a paper web around a core, the first and second rollers can easily correct the curl of the piece of paper (decurl the piece of paper), which further stabilizes the paper placement point on the paper placement part. On the other hand, when the second roller is in the second position, the pinch of the piece of paper is released, whereby the next piece of paper can smoothly enter between the first and second rollers. This prevents the leading edge of the next piece of paper from lodging on the first or second roller.

[0014]Thus, coupled with change of the second roller from the first position to the second position, the piece of paper can be further accelerated in the paper output direction. This further stabilizes the paper placement point on the paper placement part.

Problems solved by technology

If the paper placement point varies in this manner, this increases the likelihood that, particularly when pieces of paper are conveyed by a belt conveyer to transfer them such as to a collection part, the transfer is disrupted.

In this case, it is difficult to increase the output speed of the piece of paper.

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