JPH038953B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a printing device, and particularly to a printing device that can load printing paper at high speed.

(2) Background of the technology As printing devices such as line printers become faster, the ratio of paper loading time to output waiting time has become impossible to ignore. In other words, even though printing time has been shortened, paper loading still relies on manual labor such as an operator, and even if paper is loaded automatically, it is extremely time-consuming compared to the printing speed. It was hot.

Therefore, it is desired to develop a printing device that can shorten the automatic loading time of printing paper.

(3) Prior art and problems FIG. 1 is a schematic diagram of a paper conveying section. 1 is a paper hopper, 2 is a printing paper, 3 is a splicing table, 4 is an automatic loading (hereinafter referred to as autoload) table that can be moved up and down, 5 and 9 are transfer guides,
6 and 8 are guides, 7 is a photosensitive drum, 10 is a tractor presser lid, 11 is a tractor, 12 is a fixing device, 13 is a paper pull-in roller, 14 is a stacker, and 26 is a tractor drive motor. The conveyance mechanism for the printing paper 2 is as follows.

A paper 2 is pulled out from a paper hopper 1, passes through a splicing table 3, and the leading edge of the paper 2 comes to an autoload table 4. When the leading edge of the paper 2 reaches the autoload table 4, the autoload table 4 is raised and the feed hole of the paper 2 is aligned with the tractor 1.
1. Furthermore, when an autoload switch (not shown) is pressed, the tractor drive motor 26 starts rotating and the paper 2 passes between the transfer guides 5, 9 and the guide guides 6, 8, and is automatically set in the direction of the arrow up to the stacker 14. In FIG. 1, it is difficult to convey the paper 2 between the autoload table 4 and the tractor presser cover 10. This is the direction in which printing paper 2 moves when loading paper (arrow direction).
Since the photosensitive drum 17 is rotating, the printing paper 2 is particularly close to the photosensitive drum 17 in front of the guide 8.
This is because there is a possibility that the photosensitive drum 17 will not separate from the photosensitive drum 17. Therefore, the rotation speed of the tractor drive motor 26 is slowed down, and the printing paper 1
Even if the conveyance speed of the image is slowed down, the image is prevented from being caught in the photosensitive drum 17.

However, in the conventional paper automatic loading control circuit, the paper transport speed at a location where paper transport is easy is set to the same speed as the above-mentioned location where paper transport is difficult. This method takes a long time to load the paper, and its influence can no longer be ignored in high-speed line printers.

For this reason, for example, Japanese Patent Laid-Open No. 57-24280 proposes a method of automatically loading continuous paper into a printing device.

However, with this method, the continuous paper is only transported intermittently and the effective transport speed of the continuous paper is reduced, so if the transport speed of the paper is too high, the leading edge of the paper may become attached to the guide member in the transport path. There was a problem in that even if the paper collided with a slight unevenness, the paper would buckle, resulting in a paper jam.

(4) Purpose of the invention In view of the above-mentioned conventional drawbacks, the purpose of the present invention is to
The paper load time is not determined at locations where paper transport is difficult, and paper jams do not occur.
An object of the present invention is to provide a printing device that can shorten paper loading time.

(5) Structure of the Invention The object of the present invention is to include a printing unit that is provided opposite to the loaded printing paper and prints on the printing paper, and a first printing unit that conveys the printing paper toward the printing unit. and a second conveyance means for conveying the printing paper so as to discharge it from the printing section; and a control means for driving and controlling the paper conveyance section. A detection means is provided for detecting that the leading edge of the printing paper has reached the second transport means, and the control means receives the paper loading instruction and controls the printing paper loaded on the first transport means. The first conveyance means is driven to convey the printing paper at a constant first speed toward the printing section, and after the detection output from the detection means is received, the printing paper is conveyed at a first speed faster than the first speed. This is achieved by providing a printing device characterized in that the first and second conveyance means are controlled so that the paper is conveyed at a speed of 2 and loaded into the paper conveyance section.

(6) Embodiment of the invention Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of a printing device according to the present invention.

Figures 1 and 2 are numbered serially, and in both Figures 26 represents the tractor drive motor. First, when an autoload switch (not shown) is pressed, a paper autoload signal (indicated by the symbol AUTLD in the figure) is set to "1". This signal is input to the one-shot multivibrator 17. The output of the one-shot multivibrator 17 is set for a period of time from when the AUTLD signal becomes "1" to when the leading edge of the paper passes through the tractor presser cover 10.

On the other hand, the frequency dividing circuit 16 divides the frequency of the reference clock by 1/n. Therefore, the AND element 20 outputs the reference clock 1/n for a period of time set by the one-shot multivibrator 17 after the AUTLD signal becomes "1". This signal passes through the OR element 21 and is input to the pulse train generator 22. The pulse train generator 22 is set in advance so that the pulse intervals of the output signal are coarse at first, gradually become denser, and become constant intervals at a certain point.

Next, the output signal of the pulse train generator 22 is transmitted to the comparator 2.
3 (indicated by symbol U in the figure). On the other hand, the down side of the comparator 23 (symbol D in the figure)
A pulse train signal generated by a rotary detector 27 attached to a tractor drive motor 26 that drives the tractor 11 is input to the pulse train signal shown in FIG. Therefore, the output signal of the comparator 23 increases when the number of pulses output by the pulse train generator 22 is greater than the number of pulses output from the rotary detector 27, and decreases in the opposite case. That is, the comparator 23 is the pulse train generator 2
The above operation is repeated until the number of pulses output by the rotary detector 2 and the number of pulses output by the rotary detector 27 become the same.

The output signal from the comparator 23 is then converted to an analog signal through a D/A converter 24, amplified by an amplifier 25, and then applied to a tractor drive motor 26. Therefore, the tractor drive motor 26
will maintain rotation at a speed of 1/n of the reference rotation speed.

On the other hand, when the preset time in the one-shot multivibrator 17 has elapsed, the output of the one-shot multivibrator 17 becomes "0", so the output of the AND element 20 also becomes "0", but the output of the AND element 19 is used as the reference. It will now output a clock. As a result, the rotational speed of the tractor drive motor 26 from the autoload table 4 to the tractor presser cover 10 in FIG. 1 becomes 1/n, and the printing paper conveyance speed also becomes 1/n of the reference speed. Then, when the leading edge of the paper passes the tractor presser cover 10, the motor 26 rotates at the standard speed, so that the transport speed also becomes the standard speed (normal transport speed).

Here, the autoload signal AUTLD is reset by setting the time for conveying the paper from the autoload table 4 to the stacker 14 using a one-shot multivibrator (not shown), or by counting the number of pulses of the rotary detector 27. This can be done by detecting the amount of paper movement.

The time required for the leading edge of the paper to reach the tractor presser cover 10 can be set by attaching a paper detector to the tractor presser cover 10 instead of the multivibrator 17, and detecting when the leading edge of the paper has passed and controlling the speed. A similar effect can be obtained by the method of

(7) Effects of the Invention As explained above, according to the present invention, the paper transport speed is slowed down in areas where paper transport is difficult, and the paper transport speed is increased in areas where paper transport is easy. Even with a similar conveyance mechanism, there is an effect that paper jams do not occur during paper loading, and the time for paper loading can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a paper conveyance mechanism, and FIG. 2 is a block diagram showing an embodiment of a printing device according to the present invention. In the drawing, 2 is a printing paper, 4 is an autoload table, 5 and 9 are transfer guides, 6 and 8 are guide guides, 7 is a photosensitive drum, 10 is a tractor presser lid, 11 is a tractor, 16 is a frequency divider, and 17 is a one-shot multivibrator, 23 is a comparator, 2
Reference numeral 6 indicates a tractor drive motor, and reference numeral 27 indicates a rotary detector.

Claims (1)

[Scope of Claims] 1. A printing section that is provided to face loaded printing paper and prints on the printing paper; a first transport means that transports the printing paper toward the printing section; and the printing paper. A printing device comprising: a paper transport section including a second transport means for transporting the paper so as to discharge the paper from the printing section; and a control means for driving and controlling the paper transport section, the printing device comprising: a leading edge of the printing paper; is provided with a detection means for detecting that the paper has reached the second conveyance means, and the control means receives a paper loading instruction and directs the printing paper loaded in the first conveyance means toward the printing unit in a constant direction. the first conveyance means is driven to convey the printing paper at a first speed, and after the detection output from the detection means is received, the printing paper is conveyed at a second speed faster than the first speed; A printing device characterized by: controlling the first and second transport means to load the paper into the paper transport section.