Electrophotography – Remote monitoring
Reexamination Certificate
2000-07-19
2001-10-30
Royer, William J. (Department: 2852)
Electrophotography
Remote monitoring
C399S016000, C399S023000, C399S045000
Reexamination Certificate
active
06311024
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image forming apparatus, an apparatus for supplying image data to the image forming apparatus, and a method of interfacing two apparatuses.
2. Related Background Art
FIG. 1
is a schematic diagram showing the structure of an electrophotographic printer which is one example of conventional image forming apparatuses. Referring to
FIG. 1
, reference numeral
100
represents a photosensitive drum used as an electrostatic latent image storing member. A charger roller
101
is mounted over the photosensitive drum
100
for uniformly charging the surface of the drum
100
in contact therewith. A light emission means applies a light beam
104
to the surface of the photosensitive drum
100
at the charged surface downstream, in the rotation direction, of the contact position with the charger roller
101
. The light emission means is constituted by a semiconductor laser
105
for emitting the light beam
104
, a scanner
106
for scanning the light beam
104
along the surface of the drum
100
, and an optical lens
107
for adjusting the light beam to focus it on the surface of the drum
100
and form a light spot thereon. The light beam
104
is modulated with image data to form an electrostatic latent image on the drum surface. The latent image is developed by a developer
102
to form a toner image, the developer being mounted in contact with the photosensitive drum
100
further downstream, in the rotation direction, of the position where the light beam
104
is applied.
The toner image is transferred on a sheet of transfer paper by a transfer roller
103
mounted under the photosensitive drum in contact therewith. Paper sheets are stacked in a paper stacker
108
disposed in front (at the right in
FIG. 1
) of the photosensitive drum
100
. A paper feed roller
109
is disposed at the end portion of the paper stacker
108
, facing the left side toward a transport path. Although a single paper stacker is shown in
FIG. 1
, paper stackers for different paper sizes may be mounted. Between the paper feed roller
109
and transfer roller
103
, a registration roller
111
is mounted which corrects a slant transport of the paper sheet and synchronizes the image formation on the photosensitive drum
100
with the paper transport, to thereby transport the paper sheet to the transfer position at a predetermined timing. A registration tensor
110
is disposed between the registration roller
111
and paper feed roller
109
to detect a presence of the paper sheet.
The paper sheet with tie toner image still not developed is further transported to a fixing device at the back (at the left in
FIG. 1
) of the photosensitive drum
100
. The fixing device is constituted by a fixing roller
112
with a fixing device (not shown) being embedded therein and a pressure roller
113
for pressing the fixing roller
112
. The toner image on the paper sheet still not developed is developed by pressing and heating the paper sheet transported from the transfer area with the fixing roller
112
and pressure roller
113
. An ejecting paper sensor
114
is mounted at the back of the fixing area, the sensor detecting a paper sheet transported from the fixing area. A paper ejecting roller
115
is mounted at the back of the ejecting paper sensor
114
to eject the developed paper sheet.
Next, a control unit of the electrophotographic printer having the above construction will be described with reference to FIG.
2
. Referring to
FIG. 2
, reference numeral
200
represents a host computer at the outside of the electrophotographic printer. The host computer
200
converts image code data entered by a user into parallel or serial data and sends it via a communication line
201
to a controller
202
. The controller
202
develops the code data into image data to be transmitted to a printer engine
220
, and requests to start printing or paper pre-feeding by sending a command to a printer control unit
203
in the engine
220
or by reading internal data supplied from the printer control unit
203
as statuses. The controller
202
also controls a sync signal for synchronizing an image output timing with a paper transport in the printer. This controller
202
may be installed in the printer or in the host computer.
The controller
202
is connected to an operation panel
204
from which a user sets various printer modes (e.g., a margin area of an image). The operation panel is usually used in an off-line state (disconnected from the communication line to the host computer). The controller
202
connected to the host computer
200
and operation panel
204
transmits data to and from the printer control unit
203
as described above. In order to perform a drive/stop timing control of each mechanical part shown in FIG.
1
and read data supplied from each sensor, the printer control unit
203
is connected to a transporting system drive unit
205
, a high voltage system drive unit
206
, an optical system drive unit
207
, a fixing heater control unit
208
, and a sensor input unit
209
.
The transporting system drive unit
205
controls a drive/stop of various motors
210
and various rollers
211
and the high voltage system drive unit
206
controls a drive/stop of a charger
212
, a developing unit
213
, and a transfer unit
214
, respectively in response to an instruction from the printer control unit
203
. The optical system drive unit
207
controls a drive/stop of a laser
215
and a scanner
216
and the fixing heater control unit
208
controls a drive/stop of a fixing heater
217
, respectively in response to an instruction from the printer control unit
203
. The sensor input unit
209
reads data from a registration sensor
218
, an ejecting paper sensor
219
, and a paper size sensor
219
a, and supplies the data to the printer control unit
203
.
Next, signals transferred between the printer controller
202
and printer (engine) control unit
203
will be described.
Signals to be transferred between the printer controller
202
and engine control unit
203
are as in the following. A signal /CPRDY indicates a communication ready state between the printer controller
202
and engine
220
. A signal /PPRDY indicates a communication ready state between the engine control unit
203
and printer controller
202
. A signal /RDY indicates a stand-by state allowing the engine control unit
203
to start printing. A signal /PRNT is a print request signal to be issued from the printer controller
202
to the engine control unit
203
. A signal /VSREQ is a request signal for a vertical sync signal to be issued by the engine control unit
203
to the printer controller
202
. A signal /HSREQ is a request signal for a horizontal sync signal to be issued by the engine control unit
203
to the printer controller
202
. A signal /BD is a horizontal sync signal to be outputted from the engine control unit
203
to the printer controller
202
. A signal /SCLK is a sync clock signal for serial communication. A signal /CMD is a command signal to be issued from the printer controller
202
to the engine control unit
203
. A signal /CBSY is a strobe signal for a command output. A signal /STS indicates a status on the engine to be issued from the printer controller
202
in response to a command. A signal /SBSY is a signal used for outputting a status. Timings of these signals in serial communications are illustrated in FIG.
3
.
When a command /CMD is outputted from the printer controller
202
, a corresponding status /STS signal is outputted from the engine control unit
203
. The sync clock /SCLK is outputted from the printer controller
202
. It is assumed that serial communications are performed in the unit of 8-bit length and LSB is used as the parity bit.
Statuses of the engine control unit
203
in serial communications are illustrated in
FIGS. 4A
to
4
C. STATUS
0
is a basic status and indicates the fundamental state of the engine
220
, STATUS
1
and STATUS
2
indicate the details when a “call” bit is “1”. STATUS
3
Serizawa Yoji
Takahashi Masako
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Royer William J.
LandOfFree
System for detecting the status of an image forming apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System for detecting the status of an image forming apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System for detecting the status of an image forming apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2605478