JPS6224239B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a roll paper cutting device for a copying machine or the like.

Conventionally, copying machines cut roll paper by automatically reading the length of the original and cutting the transfer paper to the same length as the original, or by cutting several different cutting lengths in advance. Select the desired cutting length with the selection switch and select the desired length (A4, A3, A2, A1
etc.) is known. However, in addition to the request to cut the original to the same size or fixed size, there are cases where it is desired to add a new border or binding margin to the copy to be obtained. It is impossible to add such borders and binding margins by cutting to the same size as the manuscript, and by setting the selection switch to the specified position for the size that is one step longer using the prescribed fixed-size cutting method, they can be added. is possible, but the copy will have too many blank spaces.

An object of the present invention is to provide a roll paper cutting device that can cut the same length as the original, and also that can make the length of the transfer paper slightly longer than the original to create appropriate margins before and after the copied image on the copy. Our goal is to provide the following. The present invention will be explained below with reference to the illustrated embodiments.

In FIG. 1, 1 is a photosensitive drum, 2 is a charger, 3 is an exposure device, 4 is a developing device, 5 is a transfer charger, and 6 is a heat fixing device. When a sheet original is inserted into the original transport unit 8 from the original table 7, the original is sent to the exposure device 3 by transport rollers 9. At this time, the leading edge of the document and the length of the document are automatically read by a photoelectric document detector 10 located in front of the roller. That is, the document detector 10 outputs the document detection signal 1 for a time length l ₁ corresponding to the document length.
0' occurs.

In the paper feed section, a roll paper 11 is sent out by a paper feed roller 13 and cut by a cutter 19 into the same size as the original. As shown in FIG. 2, this paper feed roller 13 is connected to a constantly rotating motor M via a clutch CL, and the clutch CL and cutter drive rotation 18 are controlled by a pulse counter circuit 14. ing.

In FIGS. 2 and 3, a pulse generator 12 is connected to the motor M. This pulse generator 12 may be coupled to a paper feed roller 13. A clock pulse CK is constantly generated from the pulse generator 12 and input to the shift register 15 of the pulse counter circuit 14. This pulse counter circuit 14 receives the document detection signal 1 from the document detector 10.
0', it counts the clock pulses CK from the pulse generator 12 and outputs the paper feed signal 1 at the appropriate time.
4' and a cut signal 14'', respectively.The paper feed signal 14' is sent to the clutch CL to control the feeding and stopping of the paper feed, and the cut signal 14' triggers the cutter drive circuit 18, which triggers the cutter 19. Activate. FIG. 4a shows the relationship between the timing of occurrence of the document detection signal 10' and the paper feed signal 14' when cutting a roll paper to the same length as the document detection length _l1 . The time lag (t ₂ -t ₁ ) in which the paper feed signal 14' is generated with respect to the photoreceptor is for synchronizing the paper feed with respect to the rotational position of the photoreceptor (the position of the toner image). The length of time l ₂ during which the paper feed signal 14' is generated is equal to the document detection length l ₁ since this is the case of fixed-size cutting.

A paper feed amount adjustment circuit 20 is further connected to the pulse counter circuit 14 described above. As shown in FIG. 4b, this adjustment circuit 20 adjusts the feeding length _l2 to the same length as the original, as well as increasing it by several mm to several tens of mm to create margins at the front and back. This is to change the timing of the paper feeding start and stop commands from the pulse counter 14 by Δl so that the length l' ₂ can be changed.

As shown in FIG. 3, the paper feed amount adjustment circuit 20 has a paper feed adjustment amount selection switch 21, and when this is set to the 0 position, the cutting length will be the same as that of the original, and when the switch is set to 1, 2, etc. If you switch to the position, the length of the original will be longer than the original by the number of shift steps that have been changed _.
It is becoming like this. In this example, switch 2
1 consists of interlocking switches SW ₁ and SW ₂ , the common contact of switch SW ₁ is connected to the set input of flip-flop 23, and the common contact of SW ₂ is connected to inverter 22.
is connected to the reset input of the flip-flop 23 via the input terminal. Fixed contacts 0, 1, and 2 of switch SW ₁ are n of shift register 15, respectively.
The fixed contacts 0, 1, and 2 of SW ₂ are connected to the output ends of the n-1 and n-2 stages, respectively, and the fixed contacts 0, 1, and 2 of SW 2 are connected to the output ends of the n, n+1, and n+2 stages of the shift register 15, respectively. The Q output of the flip-flop 23 is taken out directly as a paper feed signal 14' and through a differentiating circuit 16 and an inverter 17 as a cut signal 14''.

As a result of this configuration, the switch
When SW ₁ and SW ₂ are switched from 0 position to 1 position,
Flip-flop 23 is connected to n of shift register 15.
It is set by the signal at the -1st stage and then reset by the signal at the (n+1)th stage. Therefore, paper feeding is started earlier by one pulse of the shift register output and stopped one pulse later than when cutting to size at the 0 position.
If switches SW ₁ and SW ₂ are set to the 2 position, the 2
The paper feeding time can be lengthened forward or backward by the pulse amount compared to the time at the 0 position. Figure 4b shows the relationship between the document detection signal 10' and the paper feed signal l' ₂ in this case, and the paper feed length is larger than the document detection length _l1 .
This shows that l' ₂ can be lengthened by an arbitrary amount ΔL.

In this way, by lengthening the start and stop of paper feeding by an arbitrary shift pulse, it is possible to create desired margins before and after the copy paper.

The switches SW ₁ and SW ₂ may not be linked, but may be independent, or only one of them may be switched.

In the example, the length of the copy is made longer than the original in order to create margins on the copy, but on the other hand, if the original has a lot of unnecessary parts and you want to make the copy paper shorter than the original, you can use the switch. SW ₁ , SW ₂
Just reverse the input signals.

It goes without saying that the number of stages selected for paper feed adjustment can be increased or the amount of paper feed adjustment per stage of the selection switch can be arbitrarily changed for correction.

The present invention can also be applied to cutting roll paper in machines other than copying machines. It is clear that it can also be used to control exposure time, charging time, development time, fixing time, etc.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a copying machine equipped with a roll cutting device of the present invention, FIG. 2 is a block diagram of the roll cutting device of the present invention, FIG. 3 is a detailed view of a part thereof, and FIG. 4a
and b are timing diagrams showing the relationship between the document detection signal and the paper feed signal at the time of cutting to a fixed size and at the time of forming a margin. 10...Document detector, 11...Roll paper, 12
...Pulse generator, 13...Paper feed roller, 14...
... Counter circuit, 15 ... Shift register, 18
... cutter drive circuit, 19 ... cutter, 20
... Paper feed amount adjustment circuit, 21 ... Selection switch, 2
3...Flip-flop.

Claims (1)

[Claims] 1 A detector that automatically reads the leading edge and length of a document, a clock pulse generator, and a clock pulse from the pulse generator that counts the clock pulses from the document detection signal from the detector and outputs a paper feed signal and a paper feed signal at a predetermined count value. It has a counter circuit that generates a cut signal, a paper feed roller that is connected to a motor via a clutch in response to the paper feed signal and feeds out the paper on the roll paper, and a cutter that cuts the paper on the roll paper in response to the cut signal. In the roll paper cutting device, a paper feed amount adjustment circuit is provided for extracting the output of the counter circuit before and after a predetermined count value as a paper feed signal and/or a cut signal via a selection switch that allows selection of a paper feed adjustment amount. A roll paper cutting device characterized by: