JPS6148197B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording device that prints out coded signals sent from a computer or the like at high speed. The printing apparatus must have a conveyance path that keeps the paper speed constant within the fixing device.

2. Description of the Related Art A non-impact printing device as shown in FIG. 1 has been developed as a device for quickly printing out graphic and character information sent from a computer or the like.

Data sent from a computer or the like is temporarily stored in buffer 1. The image forming section 15 reads out the data from the buffer 1 and forms the data image on the image forming body 2. The image is developed by a developing device 3 and transferred onto continuous paper 4 by a transfer device 5. After that, the paper 4 is sent by the tractor 6,
The image is fixed by a fixing device 7 and stored in a stacker 8. On the other hand, the image forming body 2 is neutralized by a static eliminator 11, cleaned by a cleaner device 12, and then charged by a charger 13, and this process is repeated again. Note that 9 is a hopper on which continuous paper is deposited, 10 is a paper end detector for detecting the end of the continuous paper, and 14 is an auxiliary roller.

When the trailing edge of the continuous paper 4 fed from the hopper 9 during printing passes through the trailing edge detector 10, the detector 10 detects the trailing edge. Based on this detection output, the image forming section 15 stops reading data from the buffer 1 and stops forming an image on the image forming body 2 at a well-defined point in the buffer 1 (output in units of pages). Further, the rotation of the image forming body 2, the paper feed tractor 6, and the auxiliary roller 14 is continued until the image transferred to the paper 4 passes through the fixing device 7. Note that the heating of the fixing device 7 is controlled so as to continue until the image transferred to the paper 4 passes through.

In this case, the paper is fed by a main feeding mechanism consisting of a tractor 6 and an auxiliary feeding mechanism consisting of a roller 14, and the feeding speed of the paper is determined by the feeding speed of the tractor 6 of the main feeding mechanism, and the roller 14 of the auxiliary feeding mechanism. is for constantly applying tension to the paper 4 so that it does not loosen in the fixing device 7. Therefore, the feed speed of the auxiliary feed mechanism is made faster than the feed speed of the main feed mechanism.

By the way, when the end of the paper 4 is reached, the tractor 6 of the main feeding mechanism disengages from the feed hole provided in the paper, and the paper 4 is fed only by the auxiliary feed roller 14, so that the paper 4 moves quickly through the fixing device 7. pass.

As a result, energy for fixing was insufficient, resulting in poor fixing. In particular, fixing using a flash lamp causes many problems such as the formation of unfixed areas.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing device having a conveyance path that keeps the paper passing speed in the fixing device constant until the paper on which an image has been transferred passes through the fixing device. .

This purpose is to calculate the distance from the position of the detection means that detects the end of the continuous paper to the transfer means by L ₁ ,
The sum of the path length from the transfer means to the image forming position when detecting the end of the continuous paper and the required path length when forming an image on the image forming body using the data to be printed in the buffer. L ₂ is the distance from the continuous paper main feed mechanism to the exit of the fixing means.
This is achieved by providing a printing device characterized by having a continuous paper conveyance path such that L ₁ −L ₂ ≧L ₃ holds when L ₃ .

That is, in the present invention, in the paper feeding mechanism, the paper feeding hole is engaged with the tractor of the main feeding mechanism until the image transferred onto the paper passes through the fixing device, so that the paper feeding speed is not changed. ing.

In order to use the above-mentioned conveyance path, as shown in FIG. _1. The path length from the transfer device 5 to the image forming position on the image forming body 2 at the time of end detection and the required path when forming an image using the data to be printed in the buffer 1 (for example, up to the page break) When L ₂ is the sum of the length and L ₃ is the distance from the tractor 6 of the continuous paper main feeding mechanism to the roller 14 of the auxiliary feeding mechanism at the exit of the fixing device, L ₁ −L ₂ ≧
It was installed at a position that had a continuous paper conveyance path such that L ₃ was established.

When the paper end detector 10 detects the end of the paper from the hopper 9, image formation by the image forming section 15 is interrupted at a point where the information received from the computer can be separated (for example, at a page break). The transfer device 5 transfers an image corresponding to the sum of the interrupted part recorded on the image forming body 2 and the required path length corresponding to the data length up to the page break to be printed in the buffer 1. Transcribe. Thereafter, the paper 4 with the image transferred thereto is sent to a fixing device 7 and a stacker 8. However, until the image transferred to the paper 4 passes through the fixing device 7, the paper 4 has a feed hole and a tractor 6 of the main feeding mechanism. Since the paper is fed while the two are engaged, the paper is fed at a constant speed.

Therefore, the transferred image on the paper 4 does not pass through the fixing device 7 at a high speed due to the disengagement between the tractor 6 of the main feeding mechanism and the paper feed hole at the end of the paper as in the conventional case, but rather at a constant speed. Since the toner is sent by the inverter, there is no possibility of fixation failure.

The present invention has been described above with reference to embodiments. According to the present invention, the distance from the position where the end of the continuous paper is detected to the transfer position is L ₁ , and the distance from the transfer means to the image forming position at the time of detecting the end of the continuous paper is L 1 . The sum of the path length and the required path length when forming an image on the image forming body using the data to be printed in the buffer is L ₂ ,
Determine the distance from the continuous paper main feed mechanism to the fuser exit.
When L ₃ , the paper passing speed in the fixing device can be kept constant by providing a paper end detection means at a position where the continuous paper transport path satisfies L ₁ −L ₂ ≧L ₃ . , fixing defects can be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a conventional non-impact printing device, and FIG. 2 is a diagram for explaining an embodiment of a printing device having a paper end detection device according to the present invention. In the figure, 1 is a buffer, 2 is an image forming body, 4 is a continuous paper, 5 is a transfer device, 6 is a tractor, 7 is a fixing device,
8 is a stacker, 9 is a hopper, 10 is a paper end detector, and 14 is an auxiliary roller.

Claims (1)

[Scope of Claims] 1. A buffer that temporarily stores data input from a computer, an image forming means that reads the data from the buffer and forms an image on an image forming body, and transfers the image to continuous paper. a fixing device that fixes the transferred image onto continuous paper in a non-contact manner; a continuous paper main feeding mechanism located at least near the transfer section that transports the continuous paper; an auxiliary feeding mechanism capable of feeding the continuous paper at a faster speed than the continuous paper main feeding mechanism; and a detection means that is provided in front of the paper transfer means in the paper conveyance direction and detects the end of the continuous paper. In a printing apparatus having the following, L ₁ is a distance from the position of the detection means to the transfer means, a path length from the transfer means to the image forming position at the time of end detection, and data to be printed in the buffer. When _{L 2} is the sum of _the required path length when an image is formed on _the image forming body using A printing device characterized by having a continuous paper conveyance path such that ≧L ₃ is satisfied.