JPS59111169A - Copying machine - Google Patents

Abstract

PURPOSE:To realize a high-reliability copying machine by constituting the 1st and the 2nd sensors in one body and generating a start timing signal for the control of a copy process on the basis of the outputs of those sensors. CONSTITUTION:Rollers 2 and 3 rotate at a specific speed to move a beltlike photosensitive body 1 in a direction A and when a mark M1 reaches the position of a sensor 18, the output signal S1 of a phototransistor 18b rises up to a logical level H to generate a pulse signal P1, putting an AND circuit 23 in operation. On the other hand, when a mark M2 reaches the position of the sensor 18, the phototransistor 18b outputs a signal S2 with the logical level H to generate a signal ST which indicates the start timing of the copy process control. Consequently, if the mark M1 is damaged, or if there is a flaw, etc., at, for example, a belt part B other than the mark M1, the signal ST is not generated, so the high-reliability copying machine is realized.

Description

[Detailed description of the invention] 〔Technical field〕 TECHNICAL FIELD The present invention relates to a military aircraft.

[Prior art]

Generally, in a copying machine, the movement of the photoreceptor and the value copying process are performed on the side 1.
Since it is necessary to synchronize the two, a pulse is generated using a timing disk that rotates as the photoreceptor moves, and the copying process is controlled based on the color value of this pulse.

In particular, copying machines that have joints (discontinuous parts) on the photoconductor, such as endless belt photoconductors or sheet-like photoconductors, need to perform copying operations on parts of the photoconductor that avoid these joints. A position detection mark is provided at the side end of the photoreceptor, and the timing Vζ when this mark is detected by a sensor is detected and control of the copying process is started.

However, in conventional copying machines, if the mark is peeled off, worn out, or damaged, the sensor may not be able to detect the mark and instead detect it as a mark other than the mark. Shallow shot process system (dll
This often resulted in the problem of not being able to do so.

Therefore, an attempt was made to solve this problem by providing marks for the number of OLs, but this required space to install sensors that use these marks separately, and
This caused the inconvenience of complicating the @ structure.

〔the purpose〕

An object of the present invention is to provide a copying machine that can solve the above-mentioned problems.

〔composition〕

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a diagram showing a simple embodiment of the present invention.

In the figure, 1 is a bell) ARK light body, 2 and 3 are rollers that drive the belt photoconductor 1, 4 is an optical system that optically moves the original and exposes the belt photoconductor 1, and 5 is a belt. A developing device that develops the electrostatic latent image on the photoconductor 1 with toner, 6 a transfer paper, 7 a pickup roller that sends out the transfer paper 6, 8
1 is a pair of rollers that transport the transfer paper 6 to the transfer section, 9 is a guide plate, 10 is a transfer chart for transferring the toner image on the belt photoreceptor 1-H to the transfer paper 6, and 11 is a curvature separation from the belt photoreceptor 1. 12 is a fixing device that fixes the toner image on the transfer paper 6; 13 is a pair of rollers that conveys the fixed transfer paper 6; and 14 is a storage unit for storing the fixed transfer paper 6. It is a tray that can be used.

15 removes the residual charge on the surface of the belt photoreceptor 1 (removal)
16 is a cleaner for removing residual toner on the surface of the belt photoreceptor 1; 17 is a Gf charger for uniformly charging the surface of the belt photoreceptor 1; It is arranged in liJ contact with the charging charter 17.

As shown in FIG. 2, on the side m of the belt photoreceptor 1, a reflective mark M1 and a translucent mark M2 are arranged with a predetermined path 1'jii L between them. This reflective mark Ml is formed by applying a band B coated in black over the entire circumference of the side end of the belt photoreceptor 1 to the side edge of the belt photoreceptor 1.
The transparent mark M2 is formed by forming a window in a corresponding portion of the belt photoreceptor 1, and further fitting a transparent material of the same size into the window.

Further, as shown in FIG. 3, the sensor 18 has a light emitting surface of a light emitting diode 18a and a light receiving part of a phototransistor 18b arranged side by side on the upper edge of a housing member formed in a substantially U-shape. The light emitting diode 18 is attached to the lower edge of the body member.
A light receiving portion of a phototransistor 18c is disposed opposite to the phototransistor 18c.

The sensor 18 is fixed such that the upper and lower edges of the housing member are located above and below the side edge of the belt photoreceptor 1 where the band portion B is formed.

FIG. 4 shows a circuit that generates a signal ST that announces the start timing of the close-up process control side j.

In the same figure, a pulse m T
A monostable multivibrator 22 generates a base pulse signal P of 1, and a monostable multivibrator 22 is trigged at the falling edge of the output pulse signal pl of the monostable multivibrator 21 to generate a pulse signal P2 of /4' pulse width T2. It is a monostable multivibrator.

Note that the above-mentioned base line width Tl is set to be slightly shorter than the time required for the belt photoreceptor 1 to move a distance at a predetermined speed, and υ is also set to be slightly shorter, and the time T2 is the time required for the belt photoreceptor 1 to move at a predetermined speed. The time during which the sensor 18 detects the mark M2 is also set to be slightly longer.

With the above configuration, the rollers 2 and 3 rotate at a predetermined speed, the belt photoreceptor 1 moves at a predetermined speed in the direction of arrow A, and the mark M
, reaches the position of the sensor 18, the output light of the light emitting diode 18m constituting the sensor 18 is reflected by this mark M1 and enters the phototransistor 18b, as shown in FIG. 5(a).
As shown in , the output signal S of the phototransistor 18b
! rises to logic level "H". As a result, the monostable multivibrator 21 is triggered, as shown in the figure (c).
A pulse signal P1 is generated as shown in FIG.

The pulse signal pl has a pulse width Tl after it rises.
This triggers the monostable multivibrator 22 and generates a pulse signal P2 as shown in FIG. The AND circuit 23 becomes inoperable.

Meanwhile, the belt photoreceptor 1 is moving at the same speed during this time, and when the mark M2 moves to the position of the sensor 18, the light emitted from the light emitting diode 18a passes through this mark Mz' and enters the phototransistor 18c. As a result, while the mark M2 passes the sensor 18, the phototransistor 18b is at the successive level rH as shown in FIG.
A signal S2 which becomes J is output.

As mentioned above, the pulse width TI of the pulse signal P1 is set to be slightly shorter than the time required for the belt photoreceptor 1 to move the distance, so the signal S2 as shown in FIG. At the time of rising, pulse signal P2 has already been output, and as a result, signal S2 is output to AND circuit 2.
3, it is output as a signal ST to the next stage equipment +M (the main body control section of the copying machine) (see (e) in the same figure).

In this way, it is possible to form the signal ST that announces the start timing of the overprinting process @j.

By the way, when the mark M1 is at the top, no light enters the phototransistor 18b, so the monostable multivibrator 21 is not triggered, and therefore the signal ST is not output. Furthermore, if light is incident on the phototransistor 18b due to a scratch on the band B other than the mark M1, for example, the distance between the mark M2 and the scratch becomes larger than the distance, so the signal ST is no longer generated. . For the same reason, even if the mark M2 is damaged or light is incident on the phototransistor 18e due to a scratch other than the mark Mt, the signal ST is not generated.

Therefore, it is possible to reliably prevent the copying machine from malfunctioning when there is an abnormality in the marks M1, M, or when these marks are erroneously detected.

Note that even if the positions of mark M1 and mark M2 are swapped,
The invention can be practiced. Moreover, although the above-mentioned embodiment U is a case where a belt photoreceptor is used, the present invention can also be practiced when a drum photoreceptor, a sheet-like photoreceptor, etc. are used. Furthermore, it is also possible to directly input the sensor signal to the microcomputer and use the software to detect the start timing of copying process control.

〔effect〕

As explained above, according to the present invention, it is possible to completely prevent abnormalities in copying growth control related to mark abnormalities and erroneous detection without causing the inconveniences associated with conventional devices, and to provide a highly reliable copying machine. realizable.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view showing an embodiment of a copying machine according to the present invention, FIG. 2 is a perspective view illustrating how marks and sensors are attached, and FIG. FIG. 4 is a perspective view illustrating the start timing of copying process control, and FIG.
) to (,) are waveform diagrams showing the operation of the main parts of the circuit shown in FIG. 4. 1... Belt photoreceptor, 18... Sensor, 18a...
・Light-emitting diode, 18b, 18c...Phototransistor, Ml...(reflective type) mark, M2...(1
! li photogenic) mark. Figure 1 Figure 2

Claims (1)

[Claims] a translucent mark formed on one side end of the photoconductor; a reflective mark formed at a predetermined distance from the translucent mark; a first sensor for detecting the translucent mark; 1. A copying machine comprising: a second sensor for detecting a mark; the first and second sensors are integrally configured; and the start timing of copying process control is generated based on the outputs of these sensors.