Information
-
Patent Grant
-
6674981
-
Patent Number
6,674,981
-
Date Filed
Thursday, January 17, 200222 years ago
-
Date Issued
Tuesday, January 6, 200420 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 399 45
- 399 389
- 399 370
- 399 376
- 399 81
- 271 171
- 355 75
- 358 449
-
International Classifications
-
Abstract
When a menu of “SHEET SIZE SETTING” is chosen, a main CPU scans a non-fixed-sized sheet once, and takes in a scanned image. Based on the taken-in image, the main CPU detects the size of the sheet and sets the sheet size of a selected sheet cassette. The main CPU controls image formation using the non-fixed-sized sheet set in the sheet cassette.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a digital copying machine wherein an image on an original is scanned by a scanner and printed out on paper by a printer.
In conventional digital copying machines, there are the following methods of detecting sheet sizes of paper sheets to be fed from sheet cassettes at the time of image formation:
(1) The user chooses one of sizes displayed on an operation panel of a digital copying machine.
(2) A sheet size detection mechanism is provided in a sheet cassette. In an example of the detection mechanism, the positions of side guides and end guides, which are made to match with a paper sheet, are detected stepwise.
In the case of (1), although the cost is low because the detection mechanism is not provided, it is inconvenient that the user has to input the sheet size.
In the case of (2), the machine body cost is high because the detection mechanism is required. Moreover, only fixed sizes can automatically be detected. The number of automatically detectable sizes is limited. When the size varies on the order of mm, as in the case of non-fixed sizes, input or setting is required.
Specifically, in either of the cases (1) and (2), when a paper sheet is of a non-fixed size, there is a problem that the user has to input or set the sheet size on the operation panel.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention is to provide an image forming apparatus capable of detecting and setting a sheet size, without increasing a machine body cost or imposing a load on a user.
This invention may provide an image forming apparatus having a plurality of cassettes for containing paper sheets, and forming an image on a paper sheet fed from one of the cassettes, the apparatus comprising: a designating section which designates the cassette in which a paper sheet for image formation by the image forming apparatus is to be set; an image read section which reads an image of the paper sheet to be set in the cassette designated by the designating section, when the paper sheet is placed on an original table; and a control section which executes a control to detect the size of the paper sheet on the basis of the image read by the image read section.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIG. 1
is a cross-sectional view showing an internal structure of a digital copying machine according to an image forming apparatus of the present invention;
FIG. 2
is a plan view showing the structure of an operation panel;
FIG. 3
is a block diagram schematically showing the structure of the digital copying machine;
FIG. 4
is a flow chart illustrating a non-fixed-sized sheet setting operation;
FIG. 5
shows an example in which a sheet size is displayed on a liquid crystal display section;
FIG. 6
shows an external structure of an example in which a sheet size is displayed on the cassette;
FIG. 7
shows an example of a tab sheet; and
FIG. 8
shows an example of display on the liquid crystal display section at the time of processing an image.
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will now be described with reference to the accompanying drawings.
FIG. 1
is a cross-sectional view showing an internal structure of a digital copying machine (DPPC) according to an image forming apparatus of the present invention.
In
FIG. 1
, the digital copying machine has an apparatus main body
10
. The apparatus main body
10
incorporates a scanner section
4
functioning as an image read section and a printer section
6
functioning as an image forming section.
An original table
12
formed of transparent glass, on which a read object, i.e. an original D is placed, is disposed on the upper surface of the apparatus main body
10
. An automatic document feeder
7
(hereinafter referred to as “ADF”) for automatically feeding originals D onto the original table
12
is disposed on the upper surface of the apparatus main body
10
. The ADF
7
is disposed to be opened/closed with respect to the original table
12
and serves as an original cover for bringing the original D placed on the original table
12
into close contact with the original table
12
.
The ADF
7
has an original tray
8
on which the original D is set; an empty sensor
9
for detecting the presence/absence of originals; pickup rollers
14
for picking up originals on the original tray
8
one by one; a feed roller
15
for conveying the picked-up original; an aligning roller pair
16
for aligning the leading edges of the originals; and a conveyor belt
18
disposed to cover almost the entire surface of the original table
12
. A plurality of originals set on the original tray
8
with their surfaces facing up are sequentially taken out from the lowermost page, i.e. the last page, aligned by the aligning roller pair
16
, and conveyed to a predetermined position on the original table
12
by the conveyor belt
18
.
In the ADF
7
, a reversing roller
20
, a non-reverse sensor
21
, a flapper
22
and a delivery roller
23
are disposed at the end portion on the opposite side of the aligning roller pair
16
with respect to the conveyor belt
18
. The original D whose image information has been read by a scanner section
4
(to be described later) is fed from the original table
12
by the conveyor belt
18
and delivered to an original delivery section
24
on the ADF
7
through the reversing roller
20
, flapper
21
and delivery roller
22
. To read the lower surface of the original D, the flapper
22
is switched. The original D conveyed by the conveyor belt
18
is reversed by the reversing roller
20
and fed to a predetermined position on the original table
12
again by the conveyor belt
18
.
The scanner section
4
provided in the apparatus main body
10
has an exposure lamp
25
as a light source for illuminating the original D placed on the original table
12
, and a first mirror
26
for deflecting reflection light from the original D in a predetermined direction. The exposure lamp
25
and first mirror
26
are attached to a first carriage
27
disposed under the original table
12
.
The first carriage
27
is disposed to be movable in parallel to the original table
12
and reciprocally moved under the original table
12
by a scanning motor through a toothed belt (not shown), etc.
A second carriage
28
movable in parallel to the original table
12
is disposed under the original table
12
. Second and third mirrors
30
and
31
for successively deflecting reflection light from the original D, which has been deflected by the first mirror
26
, are attached to the second carriage
28
at right angles with each other. The second carriage
28
is moved by, e.g. the toothed belt for driving the first carriage
27
along with the first carriage
27
, and moved in parallel along the original table
12
at half the speed of the first carriage.
A focusing lens
32
for focusing reflection light from the third mirror
31
mounted on the second carriage
28
, and a CCD (photoelectric conversion element)
34
for receiving the reflected light focused by the focusing lens and photoelectrically converting it are also disposed under the original table
12
. The focusing lens
32
is disposed in a plane including the optical axis of the light deflected by the third mirror
31
so as to be movable by means of a driving mechanism. The focusing lens
32
moves to focus the reflection light at a desired magnification. The CCD
34
photoelectrically converts the incoming reflection light and outputs an electrical signal corresponding to the read original D.
On the other hand, the printer section
6
has a laser exposure unit
40
functioning as a latent image forming means. The laser exposure unit
40
comprises a semiconductor laser
41
as a light source; a polygon mirror
36
as a scanning member for continuously deflecting a laser beam emitted by the semiconductor laser
41
; a polygon motor
37
as a scanning motor for rotatably driving the polygon mirror
36
at a predetermined rotational speed; and an optical system
42
for deflecting the laser beam from the polygon mirror
36
and guiding the beam to a photosensitive drum
44
(to be described later). The laser exposure unit
40
with the above structure is fixed to a support frame (not shown) of the apparatus main body
10
.
The semiconductor laser
41
is ON/OFF-controlled in accordance with the image information of the original D read by the scanner section
4
or facsimile transmission/reception document information. The laser beam is directed to the photosensitive drum
44
through the polygon mirror
36
and optical system
42
to scan the outer surface of the photosensitive drum
44
, thereby forming an electrostatic latent image on the outer peripheral surface of the photosensitive drum
44
.
The printer section
6
has the rotatable photosensitive drum
44
as an image carrier disposed almost at the center of the apparatus main body
10
. The outer peripheral surface of the photosensitive drum
44
is exposed to the laser beam from the laser exposure unit
40
, and so a desired electrostatic latent image is formed thereon. Around the photosensitive drum
44
, the following elements are arranged in the named order: a charger
45
for electrifying the outer peripheral surface of the drum
44
with a predetermined charge; a developing device
46
for supplying toner as a developer to the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum
44
to develop it at a desired image density; a transfer charger
48
, which integrally includes a separation charger
47
for separating an image formation medium, i.e. a paper sheet P, fed from a paper cassette (to be described later) from the photosensitive drum
44
, and transfers the toner image formed on the photosensitive drum
44
onto the paper sheet P; a separation gripper
49
for separating the paper sheet P from the outer peripheral surface of the photosensitive drum
44
; a cleaning unit
50
for removing toner remaining on the outer peripheral surface of the photosensitive drum
44
; and a charge erase device
51
for erasing charge on the outer peripheral surface of the photosensitive drum
44
.
An upper sheet cassette
52
, a middle sheet cassette
53
and a lower sheet cassette
54
which can be drawn out of the apparatus main body
10
are stacked at the lower portion of the apparatus main body
10
. These cassettes
52
to
54
store paper sheets P of different sizes. A large-capacity feeder
55
is disposed on one side of these cassettes. This large-capacity feeder
55
stores about 3,000 paper sheets P having a size with high use frequency, e.g. paper sheets P with A4 size. A feed cassette
57
also serving as a manual feed tray
56
is detachably attached above the large-capacity feeder
55
.
A convey path
58
extending from the sheet cassettes and large-capacity feeder
55
through a transfer section located between the photosensitive drum
44
and transfer charger
48
is formed in the apparatus main body
10
. A fixing unit
60
having a fixing lamp
60
a
is disposed at the end of the convey path
58
. A delivery port
61
is formed in the side wall of the apparatus main body
10
, which is opposed to the fixing unit
60
. A single-tray finisher
150
is attached to the delivery port
61
.
Pickup rollers
63
for taking out the paper sheets P one by one from the sheet cassette
52
,
53
,
54
,
57
or large-capacity feeder
55
are arranged near each of the upper sheet cassette
52
, middle sheet cassette
53
, lower sheet cassette
54
and feed cassette
57
and near the large-capacity feeder
55
. A number of feed roller pairs
64
for conveying the paper sheet P taken out by the pickup rollers
63
through the convey path
58
are arranged in the convey path
58
.
A registration roller pair
65
is arranged in the convey path
58
on the upstream side of the photosensitive drum
44
. The registration roller pair
65
corrects a tilt of the extracted paper sheet P, registers the leading edge of the toner image on the photosensitive drum
44
and the leading edge of the paper sheet P, and feeds the paper sheet P to the transfer section at the same speed as the speed of movement of the outer peripheral surface of the photosensitive drum
44
. A prealigning sensor
66
for detecting arrival of the paper sheet P is provided in front of the registration roller pair
65
, i.e. on the feed roller
64
side.
Each paper sheet P extracted one by one from the sheet cassette,
52
,
53
,
54
,
57
or large-capacity feeder
55
by the pickup rollers
63
is fed to the registration roller pair
65
by the feed roller pair
64
. After the leading edge of the paper sheet P is aligned by the registration roller pair
65
, the paper sheet P is fed to the transfer section.
In the transfer section, a developer image, i.e. toner image formed on the photosensitive drum
44
is transferred onto the paper sheet P by the transfer charger
48
. The paper sheet P on which the toner image has been transferred is separated from the outer peripheral surface of the photosensitive drum
44
by the function of the separation charger
47
and separation gripper
49
and conveyed to the fixing unit
60
through a conveyor belt
67
constituting part of the convey path
58
. After the developer image is melted and fixed on the paper sheet P by the fixing unit
60
, the copying paper sheet P is delivered onto the finisher
150
through the delivery port
61
by a feed roller pair
68
and a delivery roller pair
69
.
An automatic double-side unit
70
for reversing the paper sheet P which has passed through the fixing unit
60
and feeding it to the registration roller pair
65
again is provided under the convey path
58
. The automatic double-side unit
70
comprises a temporary stack
71
for temporarily stacking the paper sheets P; a reversing path
72
branched from the convey path
58
to reverse the paper sheet P which has passed through the fixing unit
60
and to guide the paper sheet P to the temporary stack
71
; pickup rollers
73
for extracting the paper sheets P stacked on the temporary stack one by one; and a feed roller
75
for feeding the extracted paper sheet P to the registration roller pair
65
through a convey path
74
. A selector gate
76
for selectively distributing the paper sheets P to the delivery port
61
or reversing path
72
is provided at the branch portion between the convey path
58
and reversing path
72
.
Where double-copying is performed, the paper sheet P which has passed through the fixing unit
60
is guided to the reversing path
72
by the selector gate
76
, temporarily stacked on the temporary stack
71
in a reversed state, and fed to the registration roller pair
65
through the convey path
74
by the pickup rollers
73
and feed roller
75
. The paper sheet P is registered by the registration roller pair
65
and fed to the transfer section again to transfer a toner image onto the reverse surface of the paper sheet P. Thereafter, the paper sheet P is delivered to the finisher
150
through the convey path
58
, fixing unit
60
and delivery rollers
69
.
The finisher
150
staples delivered copies of documents and stores them in units of a copy. Each time a paper sheet P to be stapled has been delivered from the delivery port
61
, a guide bar
151
aligns the paper sheet P to the stapling side. When all paper sheets have been delivered, a copy of paper sheets P is pressed by a paper press arm
152
and stapled by a stapler unit (not shown). Then the guide bar
151
moves downward. The stapled paper sheets P are delivered to a finisher delivery tray
154
by a finisher delivery roller
155
in units of a copy. The downward movement amount of the finisher delivery tray
154
is roughly determined in accordance with the number of paper sheets P to be delivered, and the finisher delivery tray
154
moves downward stepwise every time one copy is delivered. The guide bar
151
for aligning the delivered paper sheets P is located at such a high position that the guide bar
151
may not abut upon the already stapled paper sheets P placed on the finisher delivery tray
154
.
The finisher delivery tray
154
is connected to a shift mechanism (not shown) which shifts (e.g. in four directions: front, rear, left and right sides) in units of a copy in the sort mode.
An operation panel
80
for inputting various copy conditions, a copy start signal for starting copying operations, etc. is provided at the upper portion on the front side of the apparatus main body
10
.
As is shown in
FIG. 2
, the operation panel
80
comprises numeral keys
81
, a copy key
82
, a state display section
83
, a liquid crystal display section
84
, an original size setting key
85
, a sheet size setting key
86
, a density display section
87
, a density setting key
88
, and a magnification setting key
89
.
The numeral keys
81
are used to set the number of originals, or the number of copies.
The copy key
82
is used to instruct the start of copying.
The state display section
83
displays guidance on the state of selection of the sheet feed cassette, jamming of an original or a paper sheet, etc.
The liquid crystal display section
84
displays the number of originals and the number of copies, and also displays the copying magnification, editing, and various operational guidances. The liquid crystal display section
84
is provided with a touch panel, which enables input of various operational instructions, such as input by selection keys. For example, it displays selection keys for a photo mode, a character mode and a character/photo mode as original modes, and permits input thereof.
The original size setting key
85
is used to set the size of the original D.
The sheet size setting key
86
is used to set the size of the sheet P.
The density display section
87
displays the copy density set by the density setting key
88
.
FIG. 3
is a block diagram schematically showing electrical connection of the digital copying machine shown in FIG.
1
and flow of signals for control. In
FIG. 3
, a control system comprises three CPUs: a main CPU
91
provided in a main control section
90
; a scanner CPU
100
in the scanner section
4
; and a printer CPU
110
in the printer section
6
. The main CPU
91
performs bidirectional communication with the printer CPU
110
via a shared RAM
95
. The main CPU
91
issues an operational instruction, and the printer CPU
110
returns status data. Serial communication is performed between the printer CPU
110
and scanner CPU
100
. The printer CPU
110
issues an operational instruction, and the scanner CPU
100
returns status data.
The operation panel
80
is connected to the main CPU
91
.
The main control section
90
comprises the main CPU
91
, a ROM
92
, a RAM
93
, an NVRAM
94
, a shared RAM
95
, an image processing unit
96
, a page memory control unit
97
, a page memory
98
, a printer controller
99
, and a printer font ROM
121
.
The main CPU
91
controls the entirety of the main control section
90
. The ROM
92
stores control programs, etc. The RAM
93
temporarily stores various data.
As will be described later, the ROM
92
stores control programs for reading an image on a paper sheet and detecting the size of the sheet from the image.
The NVM (Non-Volatile RAM)
94
is a non-volatile memory backed up by a battery (not shown). Even when power is not supplied to the NVM
94
, stored data is maintained.
The shared RAM
95
is used to perform bidirectional communication between the main CPU
91
and printer CPU
110
.
The page memory controller
97
stores and reads out image information in and from the page memory
98
. The page memory
98
has areas capable of storing image information of a plurality of pages. The page memory
98
can store compressed data in units of a page, which is obtained by compressing image information from the scanner section
4
.
In addition, a compression section
87
for compressing image data is connected to the page memory controller
97
.
The printer font ROM
121
stores font data corresponding to print data.
The printer controller
99
develops print data, which is sent from an external device
122
such as a personal computer, into image data using the font data stored in the printer font ROM
121
with a resolution corresponding to resolution data added to the print data.
The scanner section
4
comprises the scanner CPU
100
for controlling the entirety of the scanner section
4
; a ROM
101
storing control programs, etc.; a data storage RAM
102
; a CCD driver
103
for driving the CCD sensor
34
; a scan motor driver
104
for controlling the rotation of a scan motor for moving the exposure lamp
25
, mirrors
26
,
27
and
28
, etc.; and an image correction unit
105
. The image correction section
105
comprises an A/D converter for converting analog signals output from the CCD sensor
34
to digital signals; a shading correction circuit for correcting a variance in the CCD sensor
34
, or a variation in threshold level due to ambient temperature variation relative to the output signal from the CCD sensor
34
; and a line memory for temporarily storing shading-corrected digital signals from the shading correction circuit.
The printer section
6
comprises the printer CPU
110
for controlling the entirety of the printer section
6
; a ROM
111
storing control programs, etc.; a data storage RAM
112
; a laser driver
113
for driving the semiconductor laser
41
; a polygon motor driver
114
(motor control device) for controlling the rotation of the polygon motor
37
of the laser exposure unit
40
; a sheet convey unit
115
for controlling conveyance of the sheet P by the convey mechanism
58
; a process control section
116
for controlling charging, developing and transferring processes using the charging device
45
, developing device
46
and transfer charger
48
; a fixation control unit
117
for controlling the fixing device
60
; and an option control unit
118
for control options.
The image process section
96
, page memory
98
, printer controller
99
, image correction section
105
, and laser driver
113
are connected over an image data bus
120
.
The operation of setting a paper sheet of a non-fixed size in the above structure will now be described with reference to a flow chart of FIG.
4
.
Assume that a non-fixed-sized paper sheet, on which an image is to be formed, is set in the digital copying machine shown in FIG.
1
.
The user chooses “SHEET SIZE SETTING” on a menu displayed on the liquid crystal display
84
of operation panel
80
(ST
1
).
The user places the non-fixed-sized sheet on the original table
12
or the original tray
8
of ADF
7
(ST
2
). Assume that the sheet has been placed on the original table
12
.
The user depresses the sheet size setting key
86
on the operation panel
80
, and chooses the cassette in which the sheet is to be set (ST
3
). Assume that the middle cassette
53
, for instance, has been chosen.
The user depresses the sheet size read icon in the liquid crystal display section
84
.
When the sheet size read icon in the liquid crystal display section
84
has been depressed (ST
4
), the main CPU
91
causes the scanner section
4
to scan the sheet once. The image on the sheet is read and stored in the page memory
98
(ST
5
). In order to detect the sheet size, it is necessary that a difference in density be present between the sheet and the area outside the sheet. Thus, when the sheet is placed on the original table
12
, the ADF
7
serving as the original holder is opened.
When the ADF
7
is used, the color of the convey belt of the ADF
7
should preferably be made different from the color of the sheet.
The main CPU
91
detects the size of the area occupied by the sheet on the basis of the image stored in the page memory
98
, and determines that the detected size is the size of the sheet to be set in the middle cassette
53
(ST
6
). Of course, if the detected size is a fixed size, the detected size is set as a fixed size.
The main CPU
91
causes the liquid crystal display section
84
of operation panel
80
to display the sheet size of the middle cassette
53
(ST
7
).
FIG. 5
shows an example in which the sheet size is displayed on the liquid crystal display section
84
. The detected sheet size, e.g. 100 mm×200 mm, is displayed at the position of the displayed cassette corresponding to the middle cassette
53
on the displayed general structure of the apparatus.
FIG. 6
shows an external structure of the middle cassette
53
. A liquid crystal display
53
b
is provided on the right side of the front face of a cassette cover
53
a
of middle cassette
53
. The main CPU
91
causes the liquid crystal display section
53
b
to display the detected sheet size, e.g. 100 mm×200 mm (ST
8
).
At last, the non-fixed-sized sheet is set in the middle cassette
53
(ST
9
). Thus, an image can be formed on the non-fixed-sized sheet.
The middle cassette
53
has the same external structure as the upper cassette
52
and lower cassette
54
.
Applied examples of the present invention will now be described.
In this invention, not only the sheet size but also the sheet shape can be detected. For example, a non-rectangular shape such as the shape of a tab sheet can be detected.
FIG. 7
shows an example of a tab sheet.
In the case of the tab sheet shown in
FIG. 7
, the size (length, width) of a tab portion has to be specified in order to effect printing on the tab portion.
In the prior art, when an image is shifted by a length of the tab portion, the user sets the amount of image shifting.
In the present invention, based on the read image of the tab sheet shown in
FIG. 7
, the main CPU
91
causes the liquid crystal display section
84
to display the image shape (to be reduced) and can detect the size of the tab portion. Thereby, printing can be effected on the tab portion without time-consuming setting.
FIG. 8
shows an example of display on the liquid crystal display section
84
at the time of image processing such as trimming or masking.
For example, when image processing for masking is performed as shown in
FIG. 8
, the main CPU
91
causes the liquid crystal display section
84
of operation panel
80
to display a reduced image of the detected sheet size (100 mm×200 mm in the Figure). Thereby, the displayed image can be used as a reference for image processing.
As has been described above, according to the embodiment of the present invention, the sheet size can be detected and set without increasing a machine body cost or imposing a load on a user.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
Claims
- 1. An image forming apparatus having a plurality of cassettes for containing paper sheets, and forming an image on a paper sheet fed from one of the cassettes, the apparatus comprising:a designating section which designates the cassette in which a paper sheet for image formation by the image forming apparatus is to be set; an image read section which reads an image of the paper sheet to be set in the cassette designated by the designating section, when said paper sheet is placed on an original table; and a control section which executes a control to detect the size of the paper sheet on the basis of the image read by the image read section and causes a display section provided on an operation panel of the image forming apparatus to display the detected size of the paper sheet, wherein the control section causes a display section provided on the cassette designated by the designating section to display the detected size of the paper sheet.
- 2. An image forming apparatus according to claim 1, wherein the control section detects the size of the paper sheet on the basis of a difference in density of the image read by the image read section.
- 3. An image forming apparatus according to claim 1, wherein the control section feeds the paper sheet from the cassette designated by the designating section and forms an image on the paper sheet in accordance with an instruction of image formation of the sheet size, when the paper sheet has been set in the cassette designated by the designating section.
- 4. An image forming apparatus having a plurality of cassettes for containing paper sheets, and forming an image on a tab sheet fed from one of the cassettes, the apparatus comprising:a designating section which designates the cassette in which a tab sheet for image formation by the image forming apparatus is to be set; an image read section which reads an image of the tab sheet to be set in the cassette designated by the designating section, when said tab sheet is placed on an original table; and a control section which causes the display section provided on the operation panel of the image forming apparatus to display the shape of the tab sheet, and detects the size of a tab section of the tab sheet.
- 5. An image forming apparatus according to claim 4, wherein the control section controls a shift of an image formation position on the tab sheet in accordance with the shape of the tab sheet.
- 6. An image forming apparatus having a plurality of cassettes for containing paper sheets, and forming an image on a paper sheet fed from one of the cassettes, the apparatus comprising:a designating section which designates the cassette in which a paper sheet for image formation by the image forming apparatus is to be set; an image read section which reads an image of the paper sheet to be set in the cassette designated by the designating section, when said paper sheet is placed on an original table; and a control section which executes a control to detect the size of the paper sheet on the basis of the image read by the image read section and causes a display section provided on an operation panel of the image forming apparatus to display the detected size of the paper sheet, wherein the control section causes the display section to display the cassette in which the paper sheet for image formation by the image forming apparatus is to be set and a sheet size detected at a display cassette which corresponds to the cassette designated by the designating section.
- 7. An image forming apparatus according to claim 6, wherein the control section detects the size of the paper sheet on the basis of a difference in density of the image read by the image read section.
- 8. An image forming apparatus according to claim 6, wherein the control section feeds the paper sheet from the cassette designated by the designating section and forms an image on the paper sheet in accordance with an instruction of image formation of the sheet size, when the paper sheet has been set in the cassette designated by the designating section.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5581344 |
Makita |
Dec 1996 |
A |
5722029 |
Tomidokoro et al. |
Feb 1998 |
A |
Foreign Referenced Citations (5)
Number |
Date |
Country |
6-0239492 |
Aug 1994 |
JP |
7-191420 |
Jul 1995 |
JP |
7-228385 |
Aug 1995 |
JP |
8-202214 |
Aug 1996 |
JP |
2000-72265 |
Mar 2000 |
JP |