JPH03288166A - Image recorder - Google Patents

Abstract

PURPOSE:To shorten fast printing time without changing a processing speed by executing control for making a feeding speed higher after a material to be recorded passes a fixing device. CONSTITUTION:By providing a detection means 10 for detecting that the material to be recorded S passes the fixing device 9 and a control means 25 for changing the feeding speed of the material S before and after the material S passes the fixing device 9, the feeding speed is made high after fixing processing is performed to the recording paper S. Thus, the fast printing time is shortened without changing the conditions of processing for forming an image and fixing the image. That is, the recording paper S to which the fixing processing has been performed is quickly ejected.

Description

[Detailed description of the invention] Ru.

Figure 2 is a sectional view of a laser beam printer 1 to which the present invention is applied. As shown in FIG. 2, the laser beam printer 1 according to this embodiment includes a cassette 3 that stores recording paper
a paper feed roller 5 that feeds recording paper from the cassette 3;
is provided.

Then, downstream of the paper feed roller 5, recording paper S and an envelope F are provided.
A pair of registration rollers 6 for synchronously conveying the images is provided.

Further, downstream of the pair of registration rollers 6, an image forming section 8 forms an image using laser light from a laser scanner section 7.
is installed. Further, a fixing device 9 is provided downstream of the image forming section 8, and a paper discharge sensor 10 is provided downstream of the fixing device 9.

A pair of conveyance rollers 11 is disposed downstream of the sheet discharge sensor 10, and a pair of sheet discharge rollers 12 and a sheet discharge tray 13 are disposed downstream of the pair of conveyance rollers 11. Further, the laser scanner section 7 includes a laser unit 14 that emits laser light and a polygon mirror 15 that scans the laser beam from the unit 14. The image forming section 8 includes a photosensitive drum 16, a pre-exposure lamp 17. - Wide charger 18. The developing device 19 is composed of a transfer charger 20 and a cleaner 21. An external device 27 is connected to the main control section 25 of the laser beam printer 1 via an interface 26 .

On the other hand, the laser beam printer 1 has a main control section 25 as shown in FIG. 3, and this main control section 25 has a microprocessor that controls the entire apparatus, a ROM that stores control programs, and stores data, etc. It is composed of RAM, gate elements, etc.

In the input/output boat of the main control unit 25, a main motor 29 for driving each roller and the photosensitive drum 16 is connected to a main motor drive circuit 28, a polygon motor 15 is connected to a polygon motor drive circuit 30, and a fixing device 9 is connected to the fixing unit 9. They are connected via a fixing device control circuit 58 that controls a halogen heater built into the device 9 to a predetermined temperature. The input boat also includes a laser beam detection circuit 34 that converts an optical signal from a laser beam detector 35 disposed on the laser beam scanning line into an electrical signal, and a cassette paper that detects the presence or absence of a sheet S in the cassette 3. An input circuit 38 that inputs the output of the presence sensor 39 and an input circuit 40 that inputs the output of a cassette size sensor 41 that detects the type of size of the sheet S stored in the cassette 3 are connected.

The output boat also includes a laser drive circuit 32 that causes the laser unit 14 to cause a semiconductor laser chip in the unit 14 to emit light based on image information from an external device 27;
A driver 36 that operates a paper feed clutch 37 that drives the paper feed roller 5 to 0N10FF, and a registration roller pair 6.
Registration roller clutch 4 that drives 0N10FF to
3, a driver 56 for driving the pre-exposure lamp 17, - a wide charger 1g,
Developer 19. A high voltage transformer control circuit 57 for driving the transfer charger 20 is connected.

Note that 59 in FIG. 3 is a low voltage power supply unit that converts commercial AC voltage into a predetermined DC voltage.

The interface 26 also provides an R interface for notifying the external device 27 that the main control unit 25 is ready for printing.
DY signal, PRNT signal from which the external device 27 instructs the main controller 25 to start printing, and the main controller 25 receives the external device 27
The main control unit 25 outputs the synchronization signal VSYNC in the vertical direction (sub-scanning direction) of the image output to request the output of the synchronization signal VSYNC in the vertical direction (sub-scanning direction). Horizontal direction of image output to be output to (
synchronization signal HSYNC in the main scanning direction).

An image signal v from which the external device 27 serially sends out a dot image in synchronization with the VSYNC signal and the H3YNC signal.
It is configured to transmit DO and has a handshake-type serial communication line, through which the external device 27 sends various commands to the main control unit 25 to cause it to print.

Next, the operation of this embodiment will be explained along the flowchart of FIG.

FIG. 1 is a flowchart focusing on paper conveyance control. When the laser beam printer 1 is powered on, the main control section 25 performs a predetermined initialization operation, and sets the RDY signal to TRUE when the recording operation becomes possible. Then, after confirming that the RDY signal is TRUE through serial communication from the external device 27, the operator
Set the NT signal to TRUE.

On the other hand, the main control unit has its own RDY signal TRUE (
When it is confirmed that step Sl) and the PRNT signal is TRUE (step S2), the sheet feeding operation is started.

Then, the pre-rotation process (step S3), that is, the polygon motor 15. The main motor 29 is started up and the electrophotographic process is initialized.

Next, when it is time to feed the cassette paper (step S
4) Turn on the paper feed clutch (step S5) and rotate the paper feed roller 5 to perform paper feeding operation. When it is time to turn off the paper feed clutch (step S6), the paper feed clutch is turned off, the rotation of the paper feed roller 5 is stopped, and the V
The REQ signal is set to TRUE (step sg).

Then, when the external device 27 confirms that the VREQ signal is TRUE and determines that image output is possible, it emits a VSYNC signal (pulse) and starts outputting the VDO signal for one page after a predetermined time. do. On this occasion,
When the main control unit 25 confirms that the VSYNC signal is TRUE (step S9), it changes the VREQ signal to FAL.
Turn on the SE (step 510), turn on the registration roller clutch (step 5ll), and transfer the recording paper S to the image forming section 8.
Transport to.

Thereafter, the main control unit 25 performs image forming processing (step 512). That is, based on the VDO signal, the laser scanner section 15 irradiates the photosensitive drum 16 with laser light,
An image is formed on the drum 16.

Note that, as shown in FIG. 4, the VDO signal for one line is output for each scan in synchronization with the horizontal periodic signal HSYNC generated by the main controller 25 based on the detection signal from the laser beam detector 35. ing.

Furthermore, the recording paper S, which is conveyed in synchronization with the image, has the image transferred by the transfer charger 20, and is then conveyed to the fixing device 9, where it undergoes a fixing process (step 513).

When the paper discharge sensor lO is turned on after the fixing process is performed (step 514), the paper discharge motor 4 is rotated at the rotation speed N. If the paper ejection sensor 10 does not turn on after a predetermined period of time (step 521), a jam is detected and the jam is processed (step 522).

Next, when the paper ejection sensor 10 is turned off, the paper ejection motor 4 is switched to the rotation speed N2 (Nz>N1), the rotation speed of the paper ejection roller pair 12 is increased, and the main motor is turned off. For example, when a step motor is used as the paper discharge motor 4, switching can be easily performed by changing the frequency of the drive pulse from the main control section 25 to the paper discharge motor drive circuit 44.

When a predetermined time has elapsed for sufficient recording paper S to be discharged to the paper discharge tray 13, the paper discharge motor 4 is turned off.

Here, if the paper ejection sensor is not turned off even after a predetermined period of time has elapsed in step S16 (step 523), it is determined that there is a jam, and jam processing is performed (step 524).

As described above, by increasing the conveyance speed after the recording paper S has undergone the fixing process, it is possible to shorten the first print time without changing the process conditions of image formation and fixing process. That is, since the user often wants to view the printed paper as soon as possible, a more user-friendly image recording apparatus can be provided by quickly discharging the recording paper that has undergone the fixing process.

FIG. 5 shows a part of a flowchart of a second embodiment to which the present invention is applied. Here, 5ioi in this figure
The previous steps are the same as those before S13 in the first embodiment, so the description is omitted.

FIG. 6 is a block diagram of the second embodiment. This figure is a block diagram of the first embodiment, with the paper ejection motor 4 and the paper ejection motor drive circuit removed from FIG. 3. ,
Others are the same as in Figure 3.

The cross-sectional view of the second embodiment is the same as the first embodiment, so its description is omitted.

The second embodiment will be explained based on FIGS. 5 and 6.

The recording sheet S on which the image has been formed is then subjected to a fixing process (step 5IOI), and the sheet discharge sensor 10 is turned on (step 5102), and when it passes the sheet discharge sensor 10, the sheet discharge sensor 10 is turned off. When the paper ejection sensor is turned off within a predetermined time (step 5103.5ill), a check is made to see if the next recording paper is being printed (step 5104).
If printing is not in progress, it is further checked whether the next recording paper is being fed (step 5105), and if not, the number of revolutions of the main motor 29 is increased (step 5106). As explained in the first embodiment, when a step motor is used, for example, the number of revolutions can be easily increased by increasing the driving frequency.

Next, when a predetermined time period has elapsed for enough recording sheets S to be discharged onto the paper discharge tray 13 (step 5107), the main motor is turned off (step S10g).

Note that the jam processing flow indicated by 5109 to 5112 in FIG. 5 is the same as S21 to S24 in FIG. 1, so a description thereof will be omitted.

As explained above, unlike the first embodiment, the second embodiment does not have a paper ejection motor exclusively for paper ejection, but instead uses a system in which image formation, fixing conveyance, and paper ejection are performed using one motor. By changing the rotation speed of the motor, it is possible to increase the conveyance speed of the recording paper after the fixing process and shorten the first print time.

[Effects of the Invention] As explained above, according to the present invention, the first print time can be shortened without changing the process speed by controlling the conveyance speed to be faster after the recording material passes through the fixing device. Therefore, a more user-friendly image recording device can be provided.

[Brief explanation of the drawing]

FIG. 1 is a flowchart in the first embodiment of the present invention, FIG. 2 is a sectional view in the first embodiment of the present invention, FIG. 3 is a block diagram in the first embodiment of the present invention, and FIG. is a timing diagram in the first embodiment of the present invention, FIG. 5 is a flowchart in the second embodiment of the present invention, and FIG. 6 is a block diagram in the second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Image recording device, 3... Paper feed cassette, 5... Paper feed roller, 9... Fixing device, lO... Paper discharge sensor, 25... Main control unit, 27... ·External device. Figure 4

Claims (1)

[Scope of Claims] 1) Detection means for detecting that the recording material has passed through the fixing device; and control for changing the conveyance speed of the recording material before and after the recording material passes through the fixing device. An image recording device characterized by comprising: means. 2) The image recording apparatus according to claim 1, wherein the control means changes the conveyance speed of another recording material when the other recording material is not being fed or image forming. 3) The image recording apparatus according to claim 1, wherein the detection means is a sensor disposed near the fixing device.