JPH01132272A - Copying machine - Google Patents

Abstract

PURPOSE:To correct copying magnification by reading the picture information of an original and processing picture element data according to copying magnification and recording the image if the set copying magnification on a sheet. CONSTITUTION:A serial picture signal read by an image sensor 13 is inputted to a picture signal processing circuit 61. The output of the picture signal processing circuit 61 is supplied to a linear density conversion circuit 62, and the linear density conversion circuit 62 converts the picture signal read by the image sensor 13 at 12 dots/mm according to the selected magnification. For instance, when the magnification is 100% (1:1), it converts 12 dots into 8 dots, and when the magnification is 75% (reduction 3/4), 12 dots into 6 dots, and when the magnification is 125% (enlarging 5/4), 12 dots into 10 dots, and outputs a serial binarization picture signal. Thus, the copying magnification can be changed correctly through a simple constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying machine, and more particularly to a copying machine capable of changing copying magnification.

In copying materials using conventional optical systems, the copying magnification is changed by moving lenses and the like. Therefore, the accuracy of the copying magnification depends on the accuracy of the lens, and if the lens accuracy is poor, the variation in the copying magnification increases, and an attempt to reduce the variation in the copying magnification requires an expensive lens.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a copying machine that has a simple configuration and can achieve accurate copying magnification.

In order to achieve this object, the present invention includes a setting means for setting a copy magnification, a reading unit for reading image information of a document,
a processing circuit that processes pixel data output from the reading unit according to the copy magnification of the setting means; and a recording device that records an image at the copy magnification set by the setting means on a sheet based on the output of the seed processing circuit. To provide a copying machine characterized by comprising the following.

Therefore, the image information of the original is read by the reading unit,
This is converted into pixel data according to a plurality of magnifications by a processing circuit and is recorded on a sheet by a recording device, so that the copying magnification of the recorded image becomes accurate.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

In FIG. 1, 1 is an embodiment of a copying machine incorporating features of the present invention. A platen 2 is arranged at the top of the copying machine 1. This platen 2 is made of transparent glass or the like, and the original picture is placed on it. This platen 2 is covered with a platen cover 3, which prevents dust and the like from adhering to the platen and protects it from damage such as scratches. The platen 1 and platen cover 2 are pivotally attached to the frame of the copying machine. A reading unit 4 is arranged below this platen 2, and this reading unit 4 is attached to a reading unit guide rail 5 so as to be able to reciprocate. The movement of the reading unit 4 takes place via a drive belt 6, which is wound around a drive shaft 7. A drive roller 8 is fixed to this drive shaft 7. This drive roller 8 receives driving force from a step motor 9 using a belt or the like. When the step motor 9 is energized, the drive roller 8 rotates, and the drive shaft 7 rotates accordingly, and this rotational motion is transmitted to the reading unit 4 via the drive belt 6 as a linear motion. Therefore, the reading unit 4 moves stepwise to the left and right under the platen 2 along the rail 5.

The reading unit 4 includes a light source 10 that illuminates the original, a reflecting mirror 11, a lens 12, and an ink sensor 13. The light source 10 extends the width of the platen in a direction perpendicular to the direction of movement of the reading unit. The light generated from the light source IO passes through a slit provided at the top of the reading unit 4 and is reflected by the original image placed on the platen according to the image information, forming an optical image. This optical image has its optical path changed by a mirror 11 and enters a lens 12 . This lens 12 focuses the incident light image onto the image sensor 13. This image sensor 13 reads information for one line having a width of 256 m+5 (84 widths) at a resolution of 12 dots/mm by arranging three photodiode arrays of 1024 columns in parallel. Moreover, other photoelectric conversion elements such as COD may be used for this image sensor 13. The image information of the document is sequentially input line by line to the image sensor 13, and is output as a continuous image electrical signal. This continuous image electrical signal is applied to the thermal recording head via a suitable image signal processing circuit, etc., which will be described later.

A recording paper supply cassette 14 is removably arranged at the lower right of the copying machine 1, and recording paper sheets 15 are arranged in a stack in this supply cassette 14. A feed roller 15 comes into contact with the top of this stack of recording paper sheets and sequentially feeds the recording paper sheets 15 one by one. This recording paper sheet 15 is automatically fed by a feeding roller 16 to an aligning roller 17 and a pitch roller 18 opposite thereto.
The nip between is fed. The feed roller 16 for automatic feeding is connected to the step motor 1 for feeding by means such as a belt.
9. This driving force transmission method is the same as that of the step motor for driving the reading unit. On the other hand, the alignment roller 17 serves to hold the recording paper sheet 15 at a suitable position. The recording paper sheet 15 is aligned with the alignment roller 1
7 and the pitch roller 18, and further passes the alignment sensor 20, the automatic feeding roller 1
6 is disconnected from the feeding step motor 19 by an electromagnetic clutch (see FIG. 3). Therefore, the subsequent conveyance of the recording paper sheet 15 is performed by the alignment roller 16. After the recording paper sheet 15 has passed, a sequence control circuit (described later) counts the number of pulses according to the step operation of the feeding step motor 19, and when the recording paper sheet 15 reaches the back roller 21, the step motor is activated. is deenergized, the interlocking rotation of the alignment roller is stopped, and the recording paper sheet 15 is left on standby there. The recording paper sheet 15 is then juxtaposed along the bank roller 21 with the ink donor web 22.

The ink donor web 22 consists of a hot-melt pigment coated on the side in contact with the recording paper sheet 15. The donor web 22 is fed from a donor web supply roll 23 and extends around the periphery of the back roller 21 and around the donor web transport roller 24 to the donor web take-up roll 25. This ink donor web winding operation is performed by an ink donor web step motor 26.
This is done by That is, the driving force of the step motor 26 is transmitted to the idler 27 by a suitable means such as a belt. The idler 27 is connected to a donor web feed roller 24 which is in contact with the back roller 21 so that the back roller 21 is stepped.

The step motor 26 operates for the first time just before the recording paper sheet 15 reaches the back roller 21, and
The ink donor web 22 and the recording paper sheet 15 are fed in parallel. This is to avoid wasteful consumption of the ink donor web.

A thermal recording head 28 is provided on the opposite side of the ink donor web 22 from the back roller so as to sandwich the ink donor web therebetween. The thermal recording head 28 has an elongated shape in which a number of resistance heating elements are arranged side by side in a direction transverse to the moving direction of the donor web, and is configured to thermally record information for 1 line read by the image sensor 13 on the recording paper sheet 15. It has become. Since energizing these heating elements at one o'clock requires a large-capacity power source, in order to downsize the power source, the power source is divided into a predetermined number of blocks and energized. One example is 6-8 dots/I
The resistor of 1,728 dots is divided into four blocks at intervals of IIIl, each block having 432 dots, and the blocks are sequentially energized to form an image. This energization control is easily performed using a diode matrix or the like. Further, the biasing width of the resistor of the thermal recording head is controlled according to the width of the recording paper used, thereby eliminating wasteful power consumption and preventing harmful transfer to the back roller 21. Furthermore, the ratio of black information of the l line to be recorded is calculated, and if it exceeds a predetermined ratio (for example, 25%), the number of block divisions described above is increased (for example, from 4 blocks to 8 blocks or 16 blocks). The energization of the resistor is controlled.

As a result, the power supply for the thermal recording head does not need to have a large capacity even when there is a lot of black information.

An automatic balancing roller 29 for removing wrinkles from the ink donor web and an idler 30 for keeping the feeding angle of the recording paper sheet constant are provided on the movement path of the ink donor web. This idler 30 is preferably arranged at a position where the web forms an angle at which the recording paper sheet 15 is smoothly fed to the back roller 21. The recording paper sheets 15 are separated downstream of the post-feeding roller 24 where thermal recording has been performed, and are output to a discharge tray 31 and stacked there. Meanwhile, the ink donor web passes through an idler 32 and is wound onto a take-up roll 25. The take-up roll 25 is provided with a slip clutch, and this clutch is driven by an idler 27 to drive the take-up roll 25 in a sliding manner.

The supply roll 23 and take-up roll 25 can be replaced by swinging an eyeing part (not shown) swingably attached to the frame of the copying machine and pivoting the platen 2 upward together with the platen cover 3 to open it. This can be done easily by doing this.

FIG. 2 shows the operation pulse 5o of the copying machine of FIG. Reference numbers 33 and 34 indicate power ON and OFF, respectively.
This is an FF switch, and when this ON switch 33 is pressed, a power indicator 35 lights up to notify the operator that the copying machine is in a working state. The number of copies selection button 36 is used to set the desired number of copies, and this set number is displayed on the set counter 38. - If you want to change the set number of copies, click 5TOPCL.
All you have to do is press the EAR button 37 and then press the number selection button 36 again. An output counter 39 is also provided to display the number of completed copies. The button 40 is a copy density selection and start switch, and depending on the density of the original, it is set to low density (LOW), medium density (MED), high density (
HI G) is selected to start the copying operation. moreover,
A magnification setting button 41 is provided to set the copy magnification, and each time this magnification setting button 41 is pressed, the magnification increases to 75%.
, 100%, and 125%, and therefore the magnification indicator 42 above it lights up. The mode indicator 43 displays the mode of the copying machine, and normally only the C0RY lamp is lit to indicate that normal copying work is being performed. When a request signal is received from the outside, the RFC lamp lights up, and an image signal is received from the outside and formed into an image on the recording paper. The 5END button 44 is a transmission button for transmitting an image signal,
When this is pressed, the 5END lamp lights up and the image signal read by the image sensor is transmitted to the outside. S/C button 45
is a button for performing transmission and copying operations. When this button 45 is pressed, the lamp S/C lights up, and at the same time, the read image signal is sent to the outside and the image signal is formed on the recording paper. . The indicator 46 lights up when an abnormality such as a jam occurs inside the copying machine, and after the abnormal condition is repaired, the 5TOP CLI! Press the AR button to turn off the light.

FIG. 3 shows a circuit diagram of the copying machine shown in FIG. 1. This circuit may be provided inside the copying machine, but may also be provided separately for miniaturization.

Reference number 13 is the image sensor shown in FIG.
In this circuit diagram, the light receiving element is divided into three blocks, and a switch 60 is used to sequentially switch between these three blocks.
It is equipped with For example, an analog switch is used as this switch 60.

A serial image signal read by the image sensor 13 is input to an image signal processing circuit 61. This image signal processing circuit performs background correction processing to remove noise (background) from the image signal, and then converts it into a white and black binary signal. Furthermore, both signal processing circuits are equipped with a white line skip function that skips reading of the next line when all lines to be read are mortar lines. For this white line skip function, it is preferable that the image sensor 13 is provided with an image receiving element that reads at least two lines simultaneously. Furthermore, the image signal processing circuit 61 is also provided with a pseudo-halftone signal generation circuit that selects a plurality of different threshold levels in the binarization processing stage of the image signal and thereby generates a pseudo-halftone signal that generates a black point signal. This makes it possible to reproduce halftones.

The output of the image signal processing circuit 61 is applied to a linear density conversion circuit 62, which has a function of converting the image signal read at 12 dots/mm by the image sensor 13 according to a selected magnification. For example, the magnification is 100
% (1:1), 12 dots become 8 dots, when the magnification is 75% (reduction, 3/4), 12 dots become 6 dots, when the magnification is 125% (enlargement, 5/4), 12 dots is converted into 10 dots, and a serial binary image signal is output.

This serial binary image signal can be transmitted to an external receiver such as a facsimile transmitter, and for this purpose an external transmission line 63 is provided.

This line may be, for example, a telephone line, an in-house communication circuit, a wireless line, or the like.

In addition to the line 63, the output of the linear density conversion circuit 62 is also connected via a line 64 to a direct image signal reproduction processing circuit 65. Switching between line 63 and line 64 is selected depending on the mode of the copying machine, and when the C0PY lamp of indicator 43 is lit, no output is output to line 63, and 5EN
When the D lamp is on, the signal is not output to line 64, and when the S/C lamp is on, it is output to lines 63 and 64 at the same time.

The image signal reproduction processing circuit 65 is an image signal reproduction processing circuit having a synchronization signal generation circuit similar to a facsimile receiver.

Therefore, it is also possible to receive image signals from the external line 66. This selection of lines 64 and 66 is based on line 63
and 64, depending on the copying machine mode. For example, when the C0PY lamp is lit, line 64 is selected, when the REC lamp is lit, only line 66 is selected, and when the 5END lamp is lit, both lines are disconnected, and the S/ When the C lamp is on, only line 64 is selected.

The image signal reproduction processing circuit 65 performs the work of rearranging the image signal data in accordance with the scanning direction of the reading unit. That is, the reading unit 4 is capable of reciprocating as described above, but in the present invention, it can read both signals not only during the forward movement but also during the backward movement. For this reason,
If the reading order during forward movement is forward, the reading order will be reversed during backward movement, so it is necessary to rearrange this data, although it is only for one line. The signal reproduction processing circuit 65 has such functions. Of course, this function is unique to the backward scanning process and is not needed during forward scanning or when receiving data from external line 66.

Further, the image signal reproduction processing circuit 65 is provided with a serial-to-parallel conversion circuit that converts the serial image signal into a parallel signal.
Create data for one line or one block thereof. Further, a switch 66 for detecting the size of the recording paper (for example, A4 or 84, etc.) is provided near the cassette 14, and a circuit is also provided for controlling the recording width of the thermal recording head 28 based on this signal. Furthermore, the head 28 described above
This circuit 65 also includes a diode matrix for controlling the heating elements in blocks, and also includes a block control circuit for increasing/decreasing the number of blocks mentioned above. Therefore, the output of this image signal reproduction processing circuit selectively energizes the heat extraction resistor of the thermal recording head 28 to heat the ink donor web 22 and form an image on the recording paper sheet 15.

The circuit 70 is a sequence control circuit, which includes a power supply 71 that turns on the light source 10 of the image reading unit, a drive circuit 72 that energizes the step motor 9 for driving the reading unit, and a drive that energizes the step motor 19 that advances the recording paper sheet. A circuit 73, a drive circuit 74 that energizes the electromagnetic clutch CL that connects and disconnects the feed roller 16 and the step motor 19, and the feed roller 24 and the back roller 21 via the idler 27.
A drive circuit 75 that energizes the step motor 26 that drives the
and the indicators of the panel 50 are sequentially controlled, and the timing of the image signal of the image signal processing circuit 61 is also controlled. This sequence control circuit 70 is
Commands from the operation panel 50, a recording paper size detection switch 67, a recording paper alignment sensor 20, and a detection switch 76 that detects whether the reading unit 4 is at the home position.
The copying operation is controlled by receiving signals from the printer.

This sequence control will be further explained in the following explanation of the copying machine operation.

The operation of the copying machine of the present invention is as follows. It is assumed that the indicator on the operation panel is the C0PY lamp lit. When one of the buttons 40 is pressed, the sequence control circuit 70, after confirming that the copying machine is operational, energizes the power source 71 to light up the light source 10 and energizes the drive circuit 72. The step motor 9 is driven to set the reading unit 4 to the home position. Sequence control circuit 70 confirms that switch 76 has set the reading unit to the home position. At this time, if the signal from the switch 76 does not arrive within a predetermined time, the copying machine stops and the indicator 46 lights up to indicate a failure.

The sequence control circuit 70 energizes the drive circuit 73 to drive the step motor 19, and continues to feed one recording paper sheet 15 from the cassette 14 by the feed roller 16 until it reaches the alignment roller 17 and alignment sensor 20. When the alignment sensor 20 detects the recording paper sheet 15, the electromagnetic clutch CL is activated, the alignment roller 16 is driven and the recording paper sheet 15 is sent by the roller, and the sequence control circuit 70 corresponds to the step operation of the step motor 19. Start counting the number of pulses, and the sheet moves to back roller 2.
1, the sheet 15 is stopped.

Next, the reading unit driving step motor 9 is activated to move the reading unit 4 forward to step-scan the original, and the image sensor 13 of the image reading unit 4 reads the original line by line. This image sensor 1. (The image signal is sent to the thermal recording head 28 via circuits 61, 62, 65. Before the thermal recording head 28 starts the recording operation, the step motor 26 is operated to move the recording paper sheet 15 and the ink. The image sent to the thermal recording head 28 is aligned with the thermal recording head with a predetermined margin placed on the recording paper sheet by the back roller 21 in close contact with the donor web 22, and preparation for recording is completed. Recording paper sheet 1 depending on the signal
5, information is recorded for each line. The amount of feed by the bank roller 21 at this time varies depending on the copying magnification, and the ratio is set to 75%:100%:125%=3:4:5.

The recorded sheet is output to a discharge tray 31, and the ink donor web is wound onto a take-up roll 25. When copying one sheet, the reading unit quickly returns to the home position. In the case of copying a large number of sheets, copying work is also performed during the forward movement. In this case, the direction read by the image sensor 13 is opposite to that in the forward stroke, so this image sensor 1
Take the read data from step 3 directly with a thermal recording spatula. When output to a computer, it is recorded as a mirror image. Therefore, this is corrected by the 1-line data sorting function of the image signal reproduction processing circuit 65 and recorded on the sheet. Note that the recording paper on which an image is formed based on the data read in this double-acting stroke has a vertically reversed orientation of the recorded image compared to the recording paper in the forward stroke, so it must be properly placed in front of the recording paper sheet ejection tray. It is preferable to provide a recording paper sheet direction changing device.

Although the operation of the copying machine in the C0PY mode has been described above, other operation modes can be easily understood from this explanation. For example, in the REC mode, image reading is not performed and only a recording operation is performed, while in the 5END mode, only image reading is performed and no recording operation is performed, and S/C (COPY/
In the 5END) mode, an image signal is transmitted from the line 63 at the same time as the copying operation is performed.

As can be seen from the above description, in the present invention, since the copy magnification is changed by processing the read image signal, the copy magnification can be changed accurately with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a thermal recording type copying machine according to the present invention. FIG. 2 is a schematic diagram of the operation panel of the copying machine shown in FIG. 1. FIG. 3 is a block diagram of the circuit of the copying machine of FIG. 1. DESCRIPTION OF SYMBOLS 1... Copying machine, 2... Platen, 3... Platen cover, 4... Reading unit, 9... Step motor for driving reading unit, lO... Light source, 12... Lens, 13... Image sensor, 14... Recording paper supply cassette, 15... Recording paper sheet, 16... Feed roller, 17... Alignment roller, 21... Bank roller, 22... Ink Donor web, 23... Ink donor web supply roll, 25... Ink donor web take-up roll, 31... Discharge tray, 50... Operation panel, 61... Image signal processing circuit, 62... - Cotton density conversion circuit, 65... Image signal reproduction processing circuit. Procedural amendment (formality) / Director General of the Japan Patent Office Yoshi 1) Takeshi Moon 1, Indication of the case Patent application No. 176345 of 1988
No. 2, Title of the invention Copying machine 3. Relationship with the person making the amendment Applicant name (549) Fuji Xerox Co., Ltd. 4, Agent 5, Date of amendment order November 29, 1988
5:, :, 2+-()

Claims (1)

[Scope of Claims] Setting means for setting a copy magnification; a reading unit for reading image information of a document; and a processing circuit for processing pixel data output by the reading unit according to the copy magnification of the setting means. A copying machine comprising: a recording device that records on a sheet an image with a copying magnification set by the setting means based on the output of the processing circuit.